Files
neovim/src/nvim/diff.c
zeertzjq 3bc9a5b5d2 vim-patch:9.1.1963: diff: missing diff size limit for xdiff (#36877)
Problem:  diff: missing diff size limit for xdiff
Solution: Impose file size limit for internal diff (xdiff)
          (Yee Cheng Chin).

Git imposes a hard cap on file size for content that it passes to xdiff
(added to Git in dcd1742e56e, defined in xdiff-interface.h), due to
integer overflow concerns in xdiff. Vim doesn't specify such a limit
right now, which means it's possible for a user to diff a large file
(1GB+) and trigger these overflow issues.

Add the same size limit (1GB minus 1MB) to Vim and simply throws an
error when Vim encounters files larger than said limit. For now, reuse
the same error message regarding internal diff failures. There is no
need to add the same limit for external diff as it's up to each tool to
error check their input to decide what is appropriate or not.

closes: vim/vim#18891

4af6d9755c

Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
2025-12-09 22:25:18 +08:00

4334 lines
126 KiB
C

/// @file diff.c
///
/// Code for diff'ing two, three or four buffers.
///
/// There are three ways to diff:
/// - Shell out to an external diff program, using files.
/// - Use the compiled-in xdiff library.
/// - Let 'diffexpr' do the work, using files.
#include <assert.h>
#include <ctype.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "auto/config.h"
#include "nvim/ascii_defs.h"
#include "nvim/autocmd.h"
#include "nvim/autocmd_defs.h"
#include "nvim/buffer.h"
#include "nvim/bufwrite.h"
#include "nvim/change.h"
#include "nvim/charset.h"
#include "nvim/cursor.h"
#include "nvim/decoration.h"
#include "nvim/diff.h"
#include "nvim/drawscreen.h"
#include "nvim/errors.h"
#include "nvim/eval/typval.h"
#include "nvim/eval/vars.h"
#include "nvim/ex_cmds.h"
#include "nvim/ex_cmds_defs.h"
#include "nvim/ex_docmd.h"
#include "nvim/extmark.h"
#include "nvim/extmark_defs.h"
#include "nvim/fileio.h"
#include "nvim/fold.h"
#include "nvim/garray.h"
#include "nvim/garray_defs.h"
#include "nvim/gettext_defs.h"
#include "nvim/globals.h"
#include "nvim/linematch.h"
#include "nvim/mark.h"
#include "nvim/mbyte.h"
#include "nvim/mbyte_defs.h"
#include "nvim/memline.h"
#include "nvim/memline_defs.h"
#include "nvim/memory.h"
#include "nvim/message.h"
#include "nvim/move.h"
#include "nvim/normal.h"
#include "nvim/option.h"
#include "nvim/option_defs.h"
#include "nvim/option_vars.h"
#include "nvim/optionstr.h"
#include "nvim/os/fs.h"
#include "nvim/os/fs_defs.h"
#include "nvim/os/os.h"
#include "nvim/os/os_defs.h"
#include "nvim/os/shell.h"
#include "nvim/path.h"
#include "nvim/pos_defs.h"
#include "nvim/strings.h"
#include "nvim/types_defs.h"
#include "nvim/ui.h"
#include "nvim/undo.h"
#include "nvim/vim_defs.h"
#include "nvim/window.h"
#include "xdiff/xdiff.h"
static bool diff_busy = false; // using diff structs, don't change them
static bool diff_need_update = false; // ex_diffupdate needs to be called
// Flags obtained from the 'diffopt' option
#define DIFF_FILLER 0x001 // display filler lines
#define DIFF_IBLANK 0x002 // ignore empty lines
#define DIFF_ICASE 0x004 // ignore case
#define DIFF_IWHITE 0x008 // ignore change in white space
#define DIFF_IWHITEALL 0x010 // ignore all white space changes
#define DIFF_IWHITEEOL 0x020 // ignore change in white space at EOL
#define DIFF_HORIZONTAL 0x040 // horizontal splits
#define DIFF_VERTICAL 0x080 // vertical splits
#define DIFF_HIDDEN_OFF 0x100 // diffoff when hidden
#define DIFF_INTERNAL 0x200 // use internal xdiff algorithm
#define DIFF_CLOSE_OFF 0x400 // diffoff when closing window
#define DIFF_FOLLOWWRAP 0x800 // follow the wrap option
#define DIFF_LINEMATCH 0x1000 // match most similar lines within diff
#define DIFF_INLINE_NONE 0x2000 // no inline highlight
#define DIFF_INLINE_SIMPLE 0x4000 // inline highlight with simple algorithm
#define DIFF_INLINE_CHAR 0x8000 // inline highlight with character diff
#define DIFF_INLINE_WORD 0x10000 // inline highlight with word diff
#define DIFF_ANCHOR 0x20000 // use 'diffanchors' to anchor the diff
#define ALL_WHITE_DIFF (DIFF_IWHITE | DIFF_IWHITEALL | DIFF_IWHITEEOL)
#define ALL_INLINE (DIFF_INLINE_NONE | DIFF_INLINE_SIMPLE | DIFF_INLINE_CHAR | DIFF_INLINE_WORD)
#define ALL_INLINE_DIFF (DIFF_INLINE_CHAR | DIFF_INLINE_WORD)
static int diff_flags = DIFF_INTERNAL | DIFF_FILLER | DIFF_CLOSE_OFF
| DIFF_LINEMATCH | DIFF_INLINE_CHAR;
static int diff_algorithm = XDF_INDENT_HEURISTIC;
static int linematch_lines = 40;
#define LBUFLEN 50 // length of line in diff file
// Max file size xdiff is eqipped to deal with. The value (1GB - 1MB) comes
// from Git's implementation.
#define MAX_XDIFF_SIZE (1024L * 1024 * 1023)
// kTrue when "diff -a" works, kFalse when it doesn't work,
// kNone when not checked yet
static TriState diff_a_works = kNone;
enum { MAX_DIFF_ANCHORS = 20, };
// used for diff input
typedef struct {
char *din_fname; // used for external diff
mmfile_t din_mmfile; // used for internal diff
} diffin_T;
// used for diff result
typedef struct {
char *dout_fname; // used for external diff
garray_T dout_ga; // used for internal diff
} diffout_T;
// used for recording hunks from xdiff
typedef struct {
linenr_T lnum_orig;
int count_orig;
linenr_T lnum_new;
int count_new;
} diffhunk_T;
// two diff inputs and one result
typedef struct {
diffin_T dio_orig; // original file input
diffin_T dio_new; // new file input
diffout_T dio_diff; // diff result
int dio_internal; // using internal diff
} diffio_T;
typedef enum {
DIFF_ED,
DIFF_UNIFIED,
DIFF_NONE,
} diffstyle_T;
#include "diff.c.generated.h"
#define FOR_ALL_DIFFBLOCKS_IN_TAB(tp, dp) \
for ((dp) = (tp)->tp_first_diff; (dp) != NULL; (dp) = (dp)->df_next)
static void clear_diffblock(diff_T *dp)
{
ga_clear(&dp->df_changes);
xfree(dp);
}
/// Called when deleting or unloading a buffer: No longer make a diff with it.
///
/// @param buf
void diff_buf_delete(buf_T *buf)
{
FOR_ALL_TABS(tp) {
int i = diff_buf_idx(buf, tp);
if (i != DB_COUNT) {
tp->tp_diffbuf[i] = NULL;
tp->tp_diff_invalid = true;
if (tp == curtab) {
// don't redraw right away, more might change or buffer state
// is invalid right now
need_diff_redraw = true;
redraw_later(curwin, UPD_VALID);
}
}
}
}
/// Check if the current buffer should be added to or removed from the list of
/// diff buffers.
///
/// @param win
void diff_buf_adjust(win_T *win)
{
if (!win->w_p_diff) {
// When there is no window showing a diff for this buffer, remove
// it from the diffs.
bool found_win = false;
FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
if ((wp->w_buffer == win->w_buffer) && wp->w_p_diff) {
found_win = true;
}
}
if (!found_win) {
int i = diff_buf_idx(win->w_buffer, curtab);
if (i != DB_COUNT) {
curtab->tp_diffbuf[i] = NULL;
curtab->tp_diff_invalid = true;
diff_redraw(true);
}
}
} else {
diff_buf_add(win->w_buffer);
}
}
/// Add a buffer to make diffs for.
///
/// Call this when a new buffer is being edited in the current window where
/// 'diff' is set.
/// Marks the current buffer as being part of the diff and requiring updating.
/// This must be done before any autocmd, because a command may use info
/// about the screen contents.
///
/// @param buf The buffer to add.
void diff_buf_add(buf_T *buf)
{
if (diff_buf_idx(buf, curtab) != DB_COUNT) {
// It's already there.
return;
}
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] == NULL) {
curtab->tp_diffbuf[i] = buf;
curtab->tp_diff_invalid = true;
diff_redraw(true);
return;
}
}
semsg(_("E96: Cannot diff more than %" PRId64 " buffers"), (int64_t)DB_COUNT);
}
/// Remove all buffers to make diffs for.
static void diff_buf_clear(void)
{
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
curtab->tp_diffbuf[i] = NULL;
curtab->tp_diff_invalid = true;
diff_redraw(true);
}
}
}
/// Find buffer "buf" in the list of diff buffers for tab page "tp".
///
/// @param buf
/// @param tp
///
/// @return its index or DB_COUNT if not found.
static int diff_buf_idx(buf_T *buf, tabpage_T *tp)
{
int idx;
for (idx = 0; idx < DB_COUNT; idx++) {
if (tp->tp_diffbuf[idx] == buf) {
break;
}
}
return idx;
}
/// Mark the diff info involving buffer "buf" as invalid, it will be updated
/// when info is requested.
///
/// @param buf
void diff_invalidate(buf_T *buf)
{
FOR_ALL_TABS(tp) {
int i = diff_buf_idx(buf, tp);
if (i != DB_COUNT) {
tp->tp_diff_invalid = true;
if (tp == curtab) {
diff_redraw(true);
}
}
}
}
/// Called by mark_adjust(): update line numbers in "buf".
///
/// @param line1
/// @param line2
/// @param amount
/// @param amount_after
void diff_mark_adjust(buf_T *buf, linenr_T line1, linenr_T line2, linenr_T amount,
linenr_T amount_after)
{
// Handle all tab pages that use "buf" in a diff.
FOR_ALL_TABS(tp) {
int idx = diff_buf_idx(buf, tp);
if (idx != DB_COUNT) {
diff_mark_adjust_tp(tp, idx, line1, line2, amount, amount_after);
}
}
}
/// Update line numbers in tab page "tp" for the buffer with index "idx".
///
/// This attempts to update the changes as much as possible:
/// When inserting/deleting lines outside of existing change blocks, create a
/// new change block and update the line numbers in following blocks.
/// When inserting/deleting lines in existing change blocks, update them.
///
/// @param tp
/// @param idx
/// @param line1
/// @param line2
/// @param amount
/// @amount_after
static void diff_mark_adjust_tp(tabpage_T *tp, int idx, linenr_T line1, linenr_T line2,
linenr_T amount, linenr_T amount_after)
{
if (diff_internal()) {
// Will update diffs before redrawing. Set _invalid to update the
// diffs themselves, set _update to also update folds properly just
// before redrawing.
// Do update marks here, it is needed for :%diffput.
tp->tp_diff_invalid = true;
tp->tp_diff_update = true;
}
linenr_T inserted;
linenr_T deleted;
if (line2 == MAXLNUM) {
// mark_adjust(99, MAXLNUM, 9, 0): insert lines
inserted = amount;
deleted = 0;
} else if (amount_after > 0) {
// mark_adjust(99, 98, MAXLNUM, 9): a change that inserts lines
inserted = amount_after;
deleted = 0;
} else {
// mark_adjust(98, 99, MAXLNUM, -2): delete lines
inserted = 0;
deleted = -amount_after;
}
diff_T *dprev = NULL;
diff_T *dp = tp->tp_first_diff;
linenr_T lnum_deleted = line1; // lnum of remaining deletion
while (true) {
// If the change is after the previous diff block and before the next
// diff block, thus not touching an existing change, create a new diff
// block. Don't do this when ex_diffgetput() is busy.
if (((dp == NULL)
|| (dp->df_lnum[idx] - 1 > line2)
|| ((line2 == MAXLNUM) && (dp->df_lnum[idx] > line1)))
&& ((dprev == NULL)
|| (dprev->df_lnum[idx] + dprev->df_count[idx] < line1))
&& !diff_busy) {
diff_T *dnext = diff_alloc_new(tp, dprev, dp);
dnext->df_lnum[idx] = line1;
dnext->df_count[idx] = inserted;
for (int i = 0; i < DB_COUNT; i++) {
if ((tp->tp_diffbuf[i] != NULL) && (i != idx)) {
if (dprev == NULL) {
dnext->df_lnum[i] = line1;
} else {
dnext->df_lnum[i] = line1
+ (dprev->df_lnum[i] + dprev->df_count[i])
- (dprev->df_lnum[idx] + dprev->df_count[idx]);
}
dnext->df_count[i] = deleted;
}
}
}
// if at end of the list, quit
if (dp == NULL) {
break;
}
// Check for these situations:
// 1 2 3
// 1 2 3
// line1 2 3 4 5
// 2 3 4 5
// 2 3 4 5
// line2 2 3 4 5
// 3 5 6
// 3 5 6
// compute last line of this change
linenr_T last = dp->df_lnum[idx] + dp->df_count[idx] - 1;
// 1. change completely above line1: nothing to do
if (last >= line1 - 1) {
if (diff_busy) {
// Currently in the middle of updating diff blocks. All we want
// is to adjust the line numbers and nothing else.
if (dp->df_lnum[idx] > line2) {
dp->df_lnum[idx] += amount_after;
}
// Advance to next entry.
dprev = dp;
dp = dp->df_next;
continue;
}
// 6. change below line2: only adjust for amount_after; also when
// "deleted" became zero when deleted all lines between two diffs.
if (dp->df_lnum[idx] - (deleted + inserted != 0) > line2) {
if (amount_after == 0) {
// nothing left to change
break;
}
dp->df_lnum[idx] += amount_after;
} else {
bool check_unchanged = false;
// 2. 3. 4. 5.: inserted/deleted lines touching this diff.
if (deleted > 0) {
linenr_T n;
linenr_T off = 0;
if (dp->df_lnum[idx] >= line1) {
if (last <= line2) {
// 4. delete all lines of diff
if ((dp->df_next != NULL)
&& (dp->df_next->df_lnum[idx] - 1 <= line2)) {
// delete continues in next diff, only do
// lines until that one
n = dp->df_next->df_lnum[idx] - lnum_deleted;
deleted -= n;
n -= dp->df_count[idx];
lnum_deleted = dp->df_next->df_lnum[idx];
} else {
n = deleted - dp->df_count[idx];
}
dp->df_count[idx] = 0;
} else {
// 5. delete lines at or just before top of diff
off = dp->df_lnum[idx] - lnum_deleted;
n = off;
dp->df_count[idx] -= line2 - dp->df_lnum[idx] + 1;
check_unchanged = true;
}
dp->df_lnum[idx] = line1;
} else {
if (last < line2) {
// 2. delete at end of diff
dp->df_count[idx] -= last - lnum_deleted + 1;
if ((dp->df_next != NULL)
&& (dp->df_next->df_lnum[idx] - 1 <= line2)) {
// delete continues in next diff, only do
// lines until that one
n = dp->df_next->df_lnum[idx] - 1 - last;
deleted -= dp->df_next->df_lnum[idx] - lnum_deleted;
lnum_deleted = dp->df_next->df_lnum[idx];
} else {
n = line2 - last;
}
check_unchanged = true;
} else {
// 3. delete lines inside the diff
n = 0;
dp->df_count[idx] -= deleted;
}
}
for (int i = 0; i < DB_COUNT; i++) {
if ((tp->tp_diffbuf[i] != NULL) && (i != idx)) {
if (dp->df_lnum[i] > off) {
dp->df_lnum[i] -= off;
} else {
dp->df_lnum[i] = 1;
}
dp->df_count[i] += n;
}
}
} else {
if (dp->df_lnum[idx] <= line1) {
// inserted lines somewhere in this diff
dp->df_count[idx] += inserted;
check_unchanged = true;
} else {
// inserted lines somewhere above this diff
dp->df_lnum[idx] += inserted;
}
}
if (check_unchanged) {
// Check if inserted lines are equal, may reduce the size of the
// diff.
//
// TODO(unknown): also check for equal lines in the middle and perhaps split
// the block.
diff_check_unchanged(tp, dp);
}
}
}
// check if this block touches the previous one, may merge them.
if ((dprev != NULL) && !dp->is_linematched && !diff_busy
&& (dprev->df_lnum[idx] + dprev->df_count[idx] == dp->df_lnum[idx])) {
for (int i = 0; i < DB_COUNT; i++) {
if (tp->tp_diffbuf[i] != NULL) {
dprev->df_count[i] += dp->df_count[i];
}
}
dp = diff_free(tp, dprev, dp);
} else {
// Advance to next entry.
dprev = dp;
dp = dp->df_next;
}
}
dprev = NULL;
dp = tp->tp_first_diff;
while (dp != NULL) {
// All counts are zero, remove this entry.
int i;
for (i = 0; i < DB_COUNT; i++) {
if ((tp->tp_diffbuf[i] != NULL) && (dp->df_count[i] != 0)) {
break;
}
}
if (i == DB_COUNT) {
dp = diff_free(tp, dprev, dp);
} else {
// Advance to next entry.
dprev = dp;
dp = dp->df_next;
}
}
if (tp == curtab) {
// Don't redraw right away, this updates the diffs, which can be slow.
need_diff_redraw = true;
// Need to recompute the scroll binding, may remove or add filler
// lines (e.g., when adding lines above w_topline). But it's slow when
// making many changes, postpone until redrawing.
diff_need_scrollbind = true;
}
}
/// Allocate a new diff block and link it between "dprev" and "dp".
///
/// @param tp
/// @param dprev
/// @param dp
///
/// @return The new diff block.
static diff_T *diff_alloc_new(tabpage_T *tp, diff_T *dprev, diff_T *dp)
{
diff_T *dnew = xcalloc(1, sizeof(*dnew));
dnew->is_linematched = false;
dnew->df_next = dp;
if (dprev == NULL) {
tp->tp_first_diff = dnew;
} else {
dprev->df_next = dnew;
}
dnew->has_changes = false;
ga_init(&dnew->df_changes, sizeof(diffline_change_T), 20);
return dnew;
}
static diff_T *diff_free(tabpage_T *tp, diff_T *dprev, diff_T *dp)
{
diff_T *ret = dp->df_next;
clear_diffblock(dp);
if (dprev == NULL) {
tp->tp_first_diff = ret;
} else {
dprev->df_next = ret;
}
return ret;
}
/// Check if the diff block "dp" can be made smaller for lines at the start and
/// end that are equal. Called after inserting lines.
///
/// This may result in a change where all buffers have zero lines, the caller
/// must take care of removing it.
///
/// @param tp
/// @param dp
static void diff_check_unchanged(tabpage_T *tp, diff_T *dp)
{
// Find the first buffers, use it as the original, compare the other
// buffer lines against this one.
int i_org;
for (i_org = 0; i_org < DB_COUNT; i_org++) {
if (tp->tp_diffbuf[i_org] != NULL) {
break;
}
}
// safety check
if (i_org == DB_COUNT) {
return;
}
if (diff_check_sanity(tp, dp) == FAIL) {
return;
}
// First check lines at the top, then at the bottom.
linenr_T off_org = 0;
linenr_T off_new = 0;
int dir = FORWARD;
while (true) {
// Repeat until a line is found which is different or the number of
// lines has become zero.
while (dp->df_count[i_org] > 0) {
// Copy the line, the next ml_get() will invalidate it.
if (dir == BACKWARD) {
off_org = dp->df_count[i_org] - 1;
}
char *line_org = xstrdup(ml_get_buf(tp->tp_diffbuf[i_org], dp->df_lnum[i_org] + off_org));
int i_new;
for (i_new = i_org + 1; i_new < DB_COUNT; i_new++) {
if (tp->tp_diffbuf[i_new] == NULL) {
continue;
}
if (dir == BACKWARD) {
off_new = dp->df_count[i_new] - 1;
}
// if other buffer doesn't have this line, it was inserted
if ((off_new < 0) || (off_new >= dp->df_count[i_new])) {
break;
}
if (diff_cmp(line_org, ml_get_buf(tp->tp_diffbuf[i_new],
dp->df_lnum[i_new] + off_new)) != 0) {
break;
}
}
xfree(line_org);
// Stop when a line isn't equal in all diff buffers.
if (i_new != DB_COUNT) {
break;
}
// Line matched in all buffers, remove it from the diff.
for (i_new = i_org; i_new < DB_COUNT; i_new++) {
if (tp->tp_diffbuf[i_new] != NULL) {
if (dir == FORWARD) {
dp->df_lnum[i_new]++;
}
dp->df_count[i_new]--;
}
}
}
if (dir == BACKWARD) {
break;
}
dir = BACKWARD;
}
}
/// Check if a diff block doesn't contain invalid line numbers.
/// This can happen when the diff program returns invalid results.
///
/// @param tp
/// @param dp
///
/// @return OK if the diff block doesn't contain invalid line numbers.
static int diff_check_sanity(tabpage_T *tp, diff_T *dp)
{
for (int i = 0; i < DB_COUNT; i++) {
if (tp->tp_diffbuf[i] != NULL) {
if (dp->df_lnum[i] + dp->df_count[i] - 1
> tp->tp_diffbuf[i]->b_ml.ml_line_count) {
return FAIL;
}
}
}
return OK;
}
/// Mark all diff buffers in the current tab page for redraw.
///
/// @param dofold Also recompute the folds
void diff_redraw(bool dofold)
{
win_T *wp_other = NULL;
bool used_max_fill_other = false;
bool used_max_fill_curwin = false;
need_diff_redraw = false;
FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
// when closing windows or wiping buffers skip invalid window
if (!wp->w_p_diff || !buf_valid(wp->w_buffer)) {
continue;
}
redraw_later(wp, UPD_SOME_VALID);
if (wp != curwin) {
wp_other = wp;
}
if (dofold && foldmethodIsDiff(wp)) {
foldUpdateAll(wp);
}
// A change may have made filler lines invalid, need to take care of
// that for other windows.
int n = diff_check_fill(wp, wp->w_topline);
if (((wp != curwin) && (wp->w_topfill > 0)) || (n > 0)) {
if (wp->w_topfill > n) {
wp->w_topfill = MAX(n, 0);
} else if ((n > 0) && (n > wp->w_topfill)) {
wp->w_topfill = n;
if (wp == curwin) {
used_max_fill_curwin = true;
} else if (wp_other != NULL) {
used_max_fill_other = true;
}
}
check_topfill(wp, false);
}
}
if (wp_other != NULL && curwin->w_p_scb) {
if (used_max_fill_curwin) {
// The current window was set to use the maximum number of filler
// lines, may need to reduce them.
diff_set_topline(wp_other, curwin);
} else if (used_max_fill_other) {
// The other window was set to use the maximum number of filler
// lines, may need to reduce them.
diff_set_topline(curwin, wp_other);
}
}
}
static void clear_diffin(diffin_T *din)
{
if (din->din_fname == NULL) {
XFREE_CLEAR(din->din_mmfile.ptr);
} else {
os_remove(din->din_fname);
}
}
static void clear_diffout(diffout_T *dout)
{
if (dout->dout_fname == NULL) {
ga_clear(&dout->dout_ga);
} else {
os_remove(dout->dout_fname);
}
}
/// Write buffer "buf" to a memory buffer.
///
/// @param buf
/// @param din
///
/// @return FAIL for failure.
static int diff_write_buffer(buf_T *buf, mmfile_t *m, linenr_T start, linenr_T end)
{
if (end < 0) {
end = buf->b_ml.ml_line_count;
}
if (buf->b_ml.ml_flags & ML_EMPTY || end < start) {
m->ptr = NULL;
m->size = 0;
return OK;
}
size_t len = 0;
// xdiff requires one big block of memory with all the text.
for (linenr_T lnum = start; lnum <= end; lnum++) {
len += (size_t)ml_get_buf_len(buf, lnum) + 1;
}
char *ptr = xmalloc(len);
m->ptr = ptr;
m->size = (int)len;
len = 0;
for (linenr_T lnum = start; lnum <= end; lnum++) {
char *s = ml_get_buf(buf, lnum);
if (diff_flags & DIFF_ICASE) {
while (*s != NUL) {
int c;
int c_len = 1;
char cbuf[MB_MAXBYTES + 1];
if (*s == NL) {
c = NUL;
} else {
// xdiff doesn't support ignoring case, fold-case the text.
c = utf_ptr2char(s);
c_len = utf_char2len(c);
c = utf_fold(c);
}
const int orig_len = utfc_ptr2len(s);
if (utf_char2bytes(c, cbuf) != c_len) {
// TODO(Bram): handle byte length difference
// One example is Å (3 bytes) and å (2 bytes).
memmove(ptr + len, s, (size_t)orig_len);
} else {
memmove(ptr + len, cbuf, (size_t)c_len);
if (orig_len > c_len) {
// Copy remaining composing characters
memmove(ptr + len + c_len, s + c_len, (size_t)(orig_len - c_len));
}
}
s += orig_len;
len += (size_t)orig_len;
}
} else {
size_t slen = strlen(s);
memmove(ptr + len, s, slen);
// NUL is represented as NL; convert
memchrsub(ptr + len, NL, NUL, slen);
len += slen;
}
ptr[len++] = NL;
}
return OK;
}
/// Write buffer "buf" to file or memory buffer.
///
/// Always use 'fileformat' set to "unix".
///
/// @param buf
/// @param din
///
/// @return FAIL for failure
static int diff_write(buf_T *buf, diffin_T *din, linenr_T start, linenr_T end)
{
if (din->din_fname == NULL) {
return diff_write_buffer(buf, &din->din_mmfile, start, end);
}
if (end < 0) {
end = buf->b_ml.ml_line_count;
}
// Always use 'fileformat' set to "unix".
int save_ml_flags = buf->b_ml.ml_flags;
char *save_ff = buf->b_p_ff;
buf->b_p_ff = xstrdup("unix");
const bool save_cmod_flags = cmdmod.cmod_flags;
// Writing the buffer is an implementation detail of performing the diff,
// so it shouldn't update the '[ and '] marks.
cmdmod.cmod_flags |= CMOD_LOCKMARKS;
if (end < start) {
// The line range specifies a completely empty file.
end = start;
buf->b_ml.ml_flags |= ML_EMPTY;
}
int r = buf_write(buf, din->din_fname, NULL,
start, end,
NULL, false, false, false, true);
cmdmod.cmod_flags = save_cmod_flags;
free_string_option(buf->b_p_ff);
buf->b_p_ff = save_ff;
buf->b_ml.ml_flags = (buf->b_ml.ml_flags & ~ML_EMPTY) | (save_ml_flags & ML_EMPTY);
return r;
}
static int lnum_compare(const void *s1, const void *s2)
{
linenr_T lnum1 = *(linenr_T *)s1;
linenr_T lnum2 = *(linenr_T *)s2;
if (lnum1 < lnum2) {
return -1;
}
if (lnum1 > lnum2) {
return 1;
}
return 0;
}
/// Update the diffs for all buffers involved.
///
/// @param dio
/// @param idx_orig
/// @param eap can be NULL
static void diff_try_update(diffio_T *dio, int idx_orig, exarg_T *eap)
{
if (dio->dio_internal) {
ga_init(&dio->dio_diff.dout_ga, sizeof(diffhunk_T), 100);
} else {
// We need three temp file names.
dio->dio_orig.din_fname = vim_tempname();
dio->dio_new.din_fname = vim_tempname();
dio->dio_diff.dout_fname = vim_tempname();
if (dio->dio_orig.din_fname == NULL
|| dio->dio_new.din_fname == NULL
|| dio->dio_diff.dout_fname == NULL) {
goto theend;
}
// Check external diff is actually working.
if (check_external_diff(dio) == FAIL) {
goto theend;
}
}
// :diffupdate!
if (eap != NULL && eap->forceit) {
for (int idx_new = idx_orig; idx_new < DB_COUNT; idx_new++) {
buf_T *buf = curtab->tp_diffbuf[idx_new];
if (buf_valid(buf)) {
buf_check_timestamp(buf);
}
}
}
// Parse and sort diff anchors if enabled
int num_anchors = INT_MAX;
linenr_T anchors[DB_COUNT][MAX_DIFF_ANCHORS];
CLEAR_FIELD(anchors);
if (diff_flags & DIFF_ANCHOR) {
for (int idx = 0; idx < DB_COUNT; idx++) {
if (curtab->tp_diffbuf[idx] == NULL) {
continue;
}
int buf_num_anchors = 0;
if (parse_diffanchors(false,
curtab->tp_diffbuf[idx],
anchors[idx],
&buf_num_anchors) != OK) {
emsg(_(e_failed_to_find_all_diff_anchors));
num_anchors = 0;
CLEAR_FIELD(anchors);
break;
}
if (buf_num_anchors < num_anchors) {
num_anchors = buf_num_anchors;
}
if (buf_num_anchors > 0) {
qsort((void *)anchors[idx],
(size_t)buf_num_anchors,
sizeof(linenr_T),
lnum_compare);
}
}
}
if (num_anchors == INT_MAX) {
num_anchors = 0;
}
// Split the files into multiple sections by anchors. Each section starts
// from one anchor (inclusive) and ends at the next anchor (exclusive).
// Diff each section separately before combining the results. If we don't
// have any anchors, we will have one big section of the entire file.
for (int anchor_i = 0; anchor_i <= num_anchors; anchor_i++) {
diff_T *orig_diff = NULL;
if (anchor_i != 0) {
orig_diff = curtab->tp_first_diff;
curtab->tp_first_diff = NULL;
}
linenr_T lnum_start = (anchor_i == 0) ? 1 : anchors[idx_orig][anchor_i - 1];
linenr_T lnum_end = (anchor_i == num_anchors) ? -1 : anchors[idx_orig][anchor_i] - 1;
// Write the first buffer to a tempfile or mmfile_t.
buf_T *buf = curtab->tp_diffbuf[idx_orig];
if (diff_write(buf, &dio->dio_orig, lnum_start, lnum_end) == FAIL) {
if (orig_diff != NULL) {
// Clean up in-progress diff blocks
curtab->tp_first_diff = orig_diff;
diff_clear(curtab);
}
goto theend;
}
// Make a difference between the first buffer and every other.
for (int idx_new = idx_orig + 1; idx_new < DB_COUNT; idx_new++) {
buf = curtab->tp_diffbuf[idx_new];
if (buf == NULL || buf->b_ml.ml_mfp == NULL) {
continue; // skip buffer that isn't loaded
}
lnum_start = anchor_i == 0 ? 1 : anchors[idx_new][anchor_i - 1];
lnum_end = anchor_i == num_anchors ? -1 : anchors[idx_new][anchor_i] - 1;
// Write the other buffer and diff with the first one.
if (diff_write(buf, &dio->dio_new, lnum_start, lnum_end) == FAIL) {
continue;
}
if (diff_file(dio) == FAIL) {
continue;
}
// Read the diff output and add each entry to the diff list.
diff_read(idx_orig, idx_new, dio);
clear_diffin(&dio->dio_new);
clear_diffout(&dio->dio_diff);
}
clear_diffin(&dio->dio_orig);
if (anchor_i != 0) {
// Combine the new diff blocks with the existing ones
for (diff_T *dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
for (int idx = 0; idx < DB_COUNT; idx++) {
if (anchors[idx][anchor_i - 1] > 0) {
dp->df_lnum[idx] += anchors[idx][anchor_i - 1] - 1;
}
}
}
if (orig_diff != NULL) {
diff_T *last_diff = orig_diff;
while (last_diff->df_next != NULL) {
last_diff = last_diff->df_next;
}
last_diff->df_next = curtab->tp_first_diff;
curtab->tp_first_diff = orig_diff;
}
}
}
theend:
xfree(dio->dio_orig.din_fname);
xfree(dio->dio_new.din_fname);
xfree(dio->dio_diff.dout_fname);
}
/// Return true if the options are set to use the internal diff library.
/// Note that if the internal diff failed for one of the buffers, the external
/// diff will be used anyway.
int diff_internal(void)
FUNC_ATTR_PURE
{
return (diff_flags & DIFF_INTERNAL) != 0 && *p_dex == NUL;
}
/// Completely update the diffs for the buffers involved.
///
/// When using the external "diff" command the buffers are written to a file,
/// also for unmodified buffers (the file could have been produced by
/// autocommands, e.g. the netrw plugin).
///
/// @param eap can be NULL
void ex_diffupdate(exarg_T *eap)
{
if (diff_busy) {
diff_need_update = true;
return;
}
int had_diffs = curtab->tp_first_diff != NULL;
// Delete all diffblocks.
diff_clear(curtab);
curtab->tp_diff_invalid = false;
// Use the first buffer as the original text.
int idx_orig;
for (idx_orig = 0; idx_orig < DB_COUNT; idx_orig++) {
if (curtab->tp_diffbuf[idx_orig] != NULL) {
break;
}
}
if (idx_orig == DB_COUNT) {
goto theend;
}
// Only need to do something when there is another buffer.
int idx_new;
for (idx_new = idx_orig + 1; idx_new < DB_COUNT; idx_new++) {
if (curtab->tp_diffbuf[idx_new] != NULL) {
break;
}
}
if (idx_new == DB_COUNT) {
goto theend;
}
// Only use the internal method if it did not fail for one of the buffers.
diffio_T diffio = { 0 };
diffio.dio_internal = diff_internal();
diff_try_update(&diffio, idx_orig, eap);
// force updating cursor position on screen
curwin->w_valid_cursor.lnum = 0;
theend:
// A redraw is needed if there were diffs and they were cleared, or there
// are diffs now, which means they got updated.
if (had_diffs || curtab->tp_first_diff != NULL) {
diff_redraw(true);
apply_autocmds(EVENT_DIFFUPDATED, NULL, NULL, false, curbuf);
}
}
/// Do a quick test if "diff" really works. Otherwise it looks like there
/// are no differences. Can't use the return value, it's non-zero when
/// there are differences.
static int check_external_diff(diffio_T *diffio)
{
// May try twice, first with "-a" and then without.
bool io_error = false;
TriState ok = kFalse;
while (true) {
ok = kFalse;
FILE *fd = os_fopen(diffio->dio_orig.din_fname, "w");
if (fd == NULL) {
io_error = true;
} else {
if (fwrite("line1\n", 6, 1, fd) != 1) {
io_error = true;
}
fclose(fd);
fd = os_fopen(diffio->dio_new.din_fname, "w");
if (fd == NULL) {
io_error = true;
} else {
if (fwrite("line2\n", 6, 1, fd) != 1) {
io_error = true;
}
fclose(fd);
fd = diff_file(diffio) == OK
? os_fopen(diffio->dio_diff.dout_fname, "r")
: NULL;
if (fd == NULL) {
io_error = true;
} else {
char linebuf[LBUFLEN];
while (true) {
// For normal diff there must be a line that contains
// "1c1". For unified diff "@@ -1 +1 @@".
if (vim_fgets(linebuf, LBUFLEN, fd)) {
break;
}
if (strncmp(linebuf, "1c1", 3) == 0
|| strncmp(linebuf, "@@ -1 +1 @@", 11) == 0) {
ok = kTrue;
}
}
fclose(fd);
}
os_remove(diffio->dio_diff.dout_fname);
os_remove(diffio->dio_new.din_fname);
}
os_remove(diffio->dio_orig.din_fname);
}
// When using 'diffexpr' break here.
if (*p_dex != NUL) {
break;
}
// If we checked if "-a" works already, break here.
if (diff_a_works != kNone) {
break;
}
diff_a_works = ok;
// If "-a" works break here, otherwise retry without "-a".
if (ok) {
break;
}
}
if (!ok) {
if (io_error) {
emsg(_("E810: Cannot read or write temp files"));
}
emsg(_("E97: Cannot create diffs"));
diff_a_works = kNone;
return FAIL;
}
return OK;
}
/// Invoke the xdiff function.
static int diff_file_internal(diffio_T *diffio)
{
xpparam_t param;
xdemitconf_t emit_cfg;
xdemitcb_t emit_cb;
CLEAR_FIELD(param);
CLEAR_FIELD(emit_cfg);
CLEAR_FIELD(emit_cb);
param.flags = (unsigned long)diff_algorithm;
if (diff_flags & DIFF_IWHITE) {
param.flags |= XDF_IGNORE_WHITESPACE_CHANGE;
}
if (diff_flags & DIFF_IWHITEALL) {
param.flags |= XDF_IGNORE_WHITESPACE;
}
if (diff_flags & DIFF_IWHITEEOL) {
param.flags |= XDF_IGNORE_WHITESPACE_AT_EOL;
}
if (diff_flags & DIFF_IBLANK) {
param.flags |= XDF_IGNORE_BLANK_LINES;
}
emit_cfg.ctxlen = 0; // don't need any diff_context here
emit_cb.priv = &diffio->dio_diff;
emit_cfg.hunk_func = xdiff_out;
if (diffio->dio_orig.din_mmfile.size > MAX_XDIFF_SIZE
|| diffio->dio_new.din_mmfile.size > MAX_XDIFF_SIZE) {
emsg(_(e_problem_creating_internal_diff));
return FAIL;
}
if (xdl_diff(&diffio->dio_orig.din_mmfile,
&diffio->dio_new.din_mmfile,
&param, &emit_cfg, &emit_cb) < 0) {
emsg(_(e_problem_creating_internal_diff));
return FAIL;
}
return OK;
}
/// Make a diff between files "tmp_orig" and "tmp_new", results in "tmp_diff".
///
/// @param dio
///
/// @return OK or FAIL
static int diff_file(diffio_T *dio)
{
char *tmp_orig = dio->dio_orig.din_fname;
char *tmp_new = dio->dio_new.din_fname;
char *tmp_diff = dio->dio_diff.dout_fname;
if (*p_dex != NUL) {
// Use 'diffexpr' to generate the diff file.
eval_diff(tmp_orig, tmp_new, tmp_diff);
return OK;
}
// Use xdiff for generating the diff.
if (dio->dio_internal) {
return diff_file_internal(dio);
}
const size_t len = (strlen(tmp_orig) + strlen(tmp_new) + strlen(tmp_diff)
+ strlen(p_srr) + 27);
char *const cmd = xmalloc(len);
// We don't want $DIFF_OPTIONS to get in the way.
if (os_env_exists("DIFF_OPTIONS", true)) {
os_unsetenv("DIFF_OPTIONS");
}
// Build the diff command and execute it. Always use -a, binary
// differences are of no use. Ignore errors, diff returns
// non-zero when differences have been found.
vim_snprintf(cmd, len, "diff %s%s%s%s%s%s%s%s %s",
diff_a_works == kFalse ? "" : "-a ",
"",
(diff_flags & DIFF_IWHITE) ? "-b " : "",
(diff_flags & DIFF_IWHITEALL) ? "-w " : "",
(diff_flags & DIFF_IWHITEEOL) ? "-Z " : "",
(diff_flags & DIFF_IBLANK) ? "-B " : "",
(diff_flags & DIFF_ICASE) ? "-i " : "",
tmp_orig, tmp_new);
append_redir(cmd, len, p_srr, tmp_diff);
block_autocmds(); // Avoid ShellCmdPost stuff
call_shell(cmd,
kShellOptFilter | kShellOptSilent | kShellOptDoOut,
NULL);
unblock_autocmds();
xfree(cmd);
return OK;
}
/// Create a new version of a file from the current buffer and a diff file.
///
/// The buffer is written to a file, also for unmodified buffers (the file
/// could have been produced by autocommands, e.g. the netrw plugin).
///
/// @param eap
void ex_diffpatch(exarg_T *eap)
{
char *buf = NULL;
win_T *old_curwin = curwin;
char *newname = NULL; // name of patched file buffer
char *esc_name = NULL;
#ifdef UNIX
char *fullname = NULL;
#endif
// We need two temp file names.
// Name of original temp file.
char *tmp_orig = vim_tempname();
// Name of patched temp file.
char *tmp_new = vim_tempname();
if ((tmp_orig == NULL) || (tmp_new == NULL)) {
goto theend;
}
// Write the current buffer to "tmp_orig".
if (buf_write(curbuf, tmp_orig, NULL,
1, curbuf->b_ml.ml_line_count,
NULL, false, false, false, true) == FAIL) {
goto theend;
}
#ifdef UNIX
// Get the absolute path of the patchfile, changing directory below.
fullname = FullName_save(eap->arg, false);
esc_name = vim_strsave_shellescape(fullname != NULL ? fullname : eap->arg, true, true);
#else
esc_name = vim_strsave_shellescape(eap->arg, true, true);
#endif
size_t buflen = strlen(tmp_orig) + strlen(esc_name) + strlen(tmp_new) + 16;
buf = xmalloc(buflen);
#ifdef UNIX
char dirbuf[MAXPATHL];
// Temporarily chdir to /tmp, to avoid patching files in the current
// directory when the patch file contains more than one patch. When we
// have our own temp dir use that instead, it will be cleaned up when we
// exit (any .rej files created). Don't change directory if we can't
// return to the current.
if ((os_dirname(dirbuf, MAXPATHL) != OK)
|| (os_chdir(dirbuf) != 0)) {
dirbuf[0] = NUL;
} else {
char *tempdir = vim_gettempdir();
if (tempdir == NULL) {
tempdir = "/tmp";
}
os_chdir(tempdir);
shorten_fnames(true);
}
#endif
if (*p_pex != NUL) {
// Use 'patchexpr' to generate the new file.
#ifdef UNIX
eval_patch(tmp_orig, (fullname != NULL ? fullname : eap->arg), tmp_new);
#else
eval_patch(tmp_orig, eap->arg, tmp_new);
#endif
} else {
// Build the patch command and execute it. Ignore errors.
vim_snprintf(buf, buflen, "patch -o %s %s < %s",
tmp_new, tmp_orig, esc_name);
block_autocmds(); // Avoid ShellCmdPost stuff
call_shell(buf, kShellOptFilter, NULL);
unblock_autocmds();
}
#ifdef UNIX
if (dirbuf[0] != NUL) {
if (os_chdir(dirbuf) != 0) {
emsg(_(e_prev_dir));
}
shorten_fnames(true);
}
#endif
// Delete any .orig or .rej file created.
STRCPY(buf, tmp_new);
strcat(buf, ".orig");
os_remove(buf);
STRCPY(buf, tmp_new);
strcat(buf, ".rej");
os_remove(buf);
// Only continue if the output file was created.
FileInfo file_info;
bool info_ok = os_fileinfo(tmp_new, &file_info);
uint64_t filesize = os_fileinfo_size(&file_info);
if (!info_ok || filesize == 0) {
emsg(_("E816: Cannot read patch output"));
} else {
if (curbuf->b_fname != NULL) {
newname = xstrnsave(curbuf->b_fname, strlen(curbuf->b_fname) + 4);
strcat(newname, ".new");
}
// don't use a new tab page, each tab page has its own diffs
cmdmod.cmod_tab = 0;
if (win_split(0, (diff_flags & DIFF_VERTICAL) ? WSP_VERT : 0) != FAIL) {
// Pretend it was a ":split fname" command
eap->cmdidx = CMD_split;
eap->arg = tmp_new;
do_exedit(eap, old_curwin);
// check that split worked and editing tmp_new
if ((curwin != old_curwin) && win_valid(old_curwin)) {
// Set 'diff', 'scrollbind' on and 'wrap' off.
diff_win_options(curwin, true);
diff_win_options(old_curwin, true);
if (newname != NULL) {
// do a ":file filename.new" on the patched buffer
eap->arg = newname;
ex_file(eap);
// Do filetype detection with the new name.
if (augroup_exists("filetypedetect")) {
do_cmdline_cmd(":doau filetypedetect BufRead");
}
}
}
}
}
theend:
if (tmp_orig != NULL) {
os_remove(tmp_orig);
}
xfree(tmp_orig);
if (tmp_new != NULL) {
os_remove(tmp_new);
}
xfree(tmp_new);
xfree(newname);
xfree(buf);
#ifdef UNIX
xfree(fullname);
#endif
xfree(esc_name);
}
/// Split the window and edit another file, setting options to show the diffs.
///
/// @param eap
void ex_diffsplit(exarg_T *eap)
{
win_T *old_curwin = curwin;
bufref_T old_curbuf;
set_bufref(&old_curbuf, curbuf);
// Need to compute w_fraction when no redraw happened yet.
validate_cursor(curwin);
set_fraction(curwin);
// don't use a new tab page, each tab page has its own diffs
cmdmod.cmod_tab = 0;
if (win_split(0, (diff_flags & DIFF_VERTICAL) ? WSP_VERT : 0) == FAIL) {
return;
}
// Pretend it was a ":split fname" command
eap->cmdidx = CMD_split;
curwin->w_p_diff = true;
do_exedit(eap, old_curwin);
if (curwin == old_curwin) { // split didn't work
return;
}
// Set 'diff', 'scrollbind' on and 'wrap' off.
diff_win_options(curwin, true);
if (win_valid(old_curwin)) {
diff_win_options(old_curwin, true);
if (bufref_valid(&old_curbuf)) {
// Move the cursor position to that of the old window.
curwin->w_cursor.lnum = diff_get_corresponding_line(old_curbuf.br_buf,
old_curwin->w_cursor.lnum);
}
}
// Now that lines are folded scroll to show the cursor at the same
// relative position.
scroll_to_fraction(curwin, curwin->w_height);
}
// Set options to show diffs for the current window.
void ex_diffthis(exarg_T *eap)
{
// Set 'diff', 'scrollbind' on and 'wrap' off.
diff_win_options(curwin, true);
}
static void set_diff_option(win_T *wp, bool value)
{
win_T *old_curwin = curwin;
curwin = wp;
curbuf = curwin->w_buffer;
curbuf->b_ro_locked++;
set_option_value_give_err(kOptDiff, BOOLEAN_OPTVAL(value), OPT_LOCAL);
curbuf->b_ro_locked--;
curwin = old_curwin;
curbuf = curwin->w_buffer;
}
/// Set options in window "wp" for diff mode.
///
/// @param addbuf Add buffer to diff.
void diff_win_options(win_T *wp, bool addbuf)
{
win_T *old_curwin = curwin;
// close the manually opened folds
curwin = wp;
newFoldLevel();
curwin = old_curwin;
// Use 'scrollbind' and 'cursorbind' when available
if (!wp->w_p_diff) {
wp->w_p_scb_save = wp->w_p_scb;
}
wp->w_p_scb = true;
if (!wp->w_p_diff) {
wp->w_p_crb_save = wp->w_p_crb;
}
wp->w_p_crb = true;
if (!(diff_flags & DIFF_FOLLOWWRAP)) {
if (!wp->w_p_diff) {
wp->w_p_wrap_save = wp->w_p_wrap;
}
wp->w_p_wrap = false;
wp->w_skipcol = 0;
}
if (!wp->w_p_diff) {
if (wp->w_p_diff_saved) {
free_string_option(wp->w_p_fdm_save);
}
wp->w_p_fdm_save = xstrdup(wp->w_p_fdm);
}
set_option_direct_for(kOptFoldmethod, STATIC_CSTR_AS_OPTVAL("diff"), OPT_LOCAL, 0,
kOptScopeWin, wp);
if (!wp->w_p_diff) {
wp->w_p_fen_save = wp->w_p_fen;
wp->w_p_fdl_save = wp->w_p_fdl;
if (wp->w_p_diff_saved) {
free_string_option(wp->w_p_fdc_save);
}
wp->w_p_fdc_save = xstrdup(wp->w_p_fdc);
}
free_string_option(wp->w_p_fdc);
wp->w_p_fdc = xstrdup("2");
assert(diff_foldcolumn >= 0 && diff_foldcolumn <= 9);
snprintf(wp->w_p_fdc, strlen(wp->w_p_fdc) + 1, "%d", diff_foldcolumn);
wp->w_p_fen = true;
wp->w_p_fdl = 0;
foldUpdateAll(wp);
// make sure topline is not halfway through a fold
changed_window_setting(wp);
if (vim_strchr(p_sbo, 'h') == NULL) {
do_cmdline_cmd("set sbo+=hor");
}
// Save the current values, to be restored in ex_diffoff().
wp->w_p_diff_saved = true;
set_diff_option(wp, true);
if (addbuf) {
diff_buf_add(wp->w_buffer);
}
redraw_later(wp, UPD_NOT_VALID);
}
/// Set options not to show diffs. For the current window or all windows.
/// Only in the current tab page.
///
/// @param eap
void ex_diffoff(exarg_T *eap)
{
bool diffwin = false;
FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
if (eap->forceit ? wp->w_p_diff : (wp == curwin)) {
// Set 'diff' off. If option values were saved in
// diff_win_options(), restore the ones whose settings seem to have
// been left over from diff mode.
set_diff_option(wp, false);
if (wp->w_p_diff_saved) {
if (wp->w_p_scb) {
wp->w_p_scb = wp->w_p_scb_save;
}
if (wp->w_p_crb) {
wp->w_p_crb = wp->w_p_crb_save;
}
if (!(diff_flags & DIFF_FOLLOWWRAP)) {
if (!wp->w_p_wrap && wp->w_p_wrap_save) {
wp->w_p_wrap = true;
wp->w_leftcol = 0;
}
}
free_string_option(wp->w_p_fdm);
wp->w_p_fdm = xstrdup(*wp->w_p_fdm_save ? wp->w_p_fdm_save : "manual");
free_string_option(wp->w_p_fdc);
wp->w_p_fdc = xstrdup(*wp->w_p_fdc_save ? wp->w_p_fdc_save : "0");
if (wp->w_p_fdl == 0) {
wp->w_p_fdl = wp->w_p_fdl_save;
}
// Only restore 'foldenable' when 'foldmethod' is not
// "manual", otherwise we continue to show the diff folds.
if (wp->w_p_fen) {
wp->w_p_fen = foldmethodIsManual(wp) ? false : wp->w_p_fen_save;
}
foldUpdateAll(wp);
}
// remove filler lines
wp->w_topfill = 0;
// make sure topline is not halfway a fold and cursor is
// invalidated
changed_window_setting(wp);
// Note: 'sbo' is not restored, it's a global option.
diff_buf_adjust(wp);
}
diffwin |= wp->w_p_diff;
}
// Also remove hidden buffers from the list.
if (eap->forceit) {
diff_buf_clear();
}
if (!diffwin) {
diff_need_update = false;
curtab->tp_diff_invalid = false;
curtab->tp_diff_update = false;
diff_clear(curtab);
}
// Remove "hor" from 'scrollopt' if there are no diff windows left.
if (!diffwin && (vim_strchr(p_sbo, 'h') != NULL)) {
do_cmdline_cmd("set sbo-=hor");
}
}
static bool extract_hunk_internal(diffout_T *dout, diffhunk_T *hunk, int *line_idx)
{
bool eof = *line_idx >= dout->dout_ga.ga_len;
if (!eof) {
*hunk = ((diffhunk_T *)dout->dout_ga.ga_data)[(*line_idx)++];
}
return eof;
}
// Extract hunk by parsing the diff output from file and calculate the diffstyle.
static bool extract_hunk(FILE *fd, diffhunk_T *hunk, diffstyle_T *diffstyle)
{
while (true) {
char line[LBUFLEN]; // only need to hold the diff line
if (vim_fgets(line, LBUFLEN, fd)) {
return true; // end of file
}
if (*diffstyle == DIFF_NONE) {
// Determine diff style.
// ed like diff looks like this:
// {first}[,{last}]c{first}[,{last}]
// {first}a{first}[,{last}]
// {first}[,{last}]d{first}
//
// unified diff looks like this:
// --- file1 2018-03-20 13:23:35.783153140 +0100
// +++ file2 2018-03-20 13:23:41.183156066 +0100
// @@ -1,3 +1,5 @@
if (isdigit((uint8_t)(*line))) {
*diffstyle = DIFF_ED;
} else if ((strncmp(line, "@@ ", 3) == 0)) {
*diffstyle = DIFF_UNIFIED;
} else if ((strncmp(line, "--- ", 4) == 0)
&& (vim_fgets(line, LBUFLEN, fd) == 0)
&& (strncmp(line, "+++ ", 4) == 0)
&& (vim_fgets(line, LBUFLEN, fd) == 0)
&& (strncmp(line, "@@ ", 3) == 0)) {
*diffstyle = DIFF_UNIFIED;
} else {
// Format not recognized yet, skip over this line. Cygwin diff
// may put a warning at the start of the file.
continue;
}
}
if (*diffstyle == DIFF_ED) {
if (!isdigit((uint8_t)(*line))) {
continue; // not the start of a diff block
}
if (parse_diff_ed(line, hunk) == FAIL) {
continue;
}
} else {
assert(*diffstyle == DIFF_UNIFIED);
if (strncmp(line, "@@ ", 3) != 0) {
continue; // not the start of a diff block
}
if (parse_diff_unified(line, hunk) == FAIL) {
continue;
}
}
// Successfully parsed diff output, can return
return false;
}
}
static void process_hunk(diff_T **dpp, diff_T **dprevp, int idx_orig, int idx_new, diffhunk_T *hunk,
bool *notsetp)
{
diff_T *dp = *dpp;
diff_T *dprev = *dprevp;
// Go over blocks before the change, for which orig and new are equal.
// Copy blocks from orig to new.
while (dp != NULL
&& hunk->lnum_orig > dp->df_lnum[idx_orig] + dp->df_count[idx_orig]) {
if (*notsetp) {
diff_copy_entry(dprev, dp, idx_orig, idx_new);
}
dprev = dp;
dp = dp->df_next;
*notsetp = true;
}
if ((dp != NULL)
&& (hunk->lnum_orig <= dp->df_lnum[idx_orig] + dp->df_count[idx_orig])
&& (hunk->lnum_orig + hunk->count_orig >= dp->df_lnum[idx_orig])) {
// New block overlaps with existing block(s).
// First find last block that overlaps.
diff_T *dpl;
for (dpl = dp; dpl->df_next != NULL; dpl = dpl->df_next) {
if (hunk->lnum_orig + hunk->count_orig < dpl->df_next->df_lnum[idx_orig]) {
break;
}
}
// If the newly found block starts before the old one, set the
// start back a number of lines.
linenr_T off = dp->df_lnum[idx_orig] - hunk->lnum_orig;
if (off > 0) {
for (int i = idx_orig; i < idx_new; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
dp->df_lnum[i] -= off;
dp->df_count[i] += off;
}
}
dp->df_lnum[idx_new] = hunk->lnum_new;
dp->df_count[idx_new] = (linenr_T)hunk->count_new;
} else if (*notsetp) {
// new block inside existing one, adjust new block
dp->df_lnum[idx_new] = hunk->lnum_new + off;
dp->df_count[idx_new] = (linenr_T)hunk->count_new - off;
} else {
// second overlap of new block with existing block
// if this hunk has different orig/new counts, adjust
// the diff block size first. When we handled the first hunk we
// would have expanded it to fit, without knowing that this
// hunk exists
int orig_size_in_dp = MIN(hunk->count_orig,
dp->df_lnum[idx_orig] +
dp->df_count[idx_orig] - hunk->lnum_orig);
int size_diff = hunk->count_new - orig_size_in_dp;
dp->df_count[idx_new] += size_diff;
// grow existing block to include the overlap completely
off = hunk->lnum_new + hunk->count_new
- (dp->df_lnum[idx_new] + dp->df_count[idx_new]);
if (off > 0) {
dp->df_count[idx_new] += off;
}
}
// Adjust the size of the block to include all the lines to the
// end of the existing block or the new diff, whatever ends last.
off = (hunk->lnum_orig + (linenr_T)hunk->count_orig)
- (dpl->df_lnum[idx_orig] + dpl->df_count[idx_orig]);
if (off < 0) {
// new change ends in existing block, adjust the end. We only
// need to do this once per block or we will over-adjust.
if (*notsetp || dp != dpl) {
// adjusting by 'off' here is only correct if
// there is not another hunk in this block. we
// adjust for this when we encounter a second
// overlap later.
dp->df_count[idx_new] += -off;
}
off = 0;
}
for (int i = idx_orig; i < idx_new; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
dp->df_count[i] = dpl->df_lnum[i] + dpl->df_count[i]
- dp->df_lnum[i] + off;
}
}
// Delete the diff blocks that have been merged into one.
diff_T *dn = dp->df_next;
dp->df_next = dpl->df_next;
while (dn != dp->df_next) {
dpl = dn->df_next;
clear_diffblock(dn);
dn = dpl;
}
} else {
// Allocate a new diffblock.
dp = diff_alloc_new(curtab, dprev, dp);
dp->df_lnum[idx_orig] = hunk->lnum_orig;
dp->df_count[idx_orig] = (linenr_T)hunk->count_orig;
dp->df_lnum[idx_new] = hunk->lnum_new;
dp->df_count[idx_new] = (linenr_T)hunk->count_new;
// Set values for other buffers, these must be equal to the
// original buffer, otherwise there would have been a change
// already.
for (int i = idx_orig + 1; i < idx_new; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
diff_copy_entry(dprev, dp, idx_orig, i);
}
}
}
*notsetp = false; // "*dp" has been set
*dpp = dp;
*dprevp = dprev;
}
/// Read the diff output and add each entry to the diff list.
///
/// @param idx_orig idx of original file
/// @param idx_new idx of new file
/// @dout diff output
static void diff_read(int idx_orig, int idx_new, diffio_T *dio)
{
FILE *fd = NULL;
int line_hunk_idx = 0; // line or hunk index
diff_T *dprev = NULL;
diff_T *dp = curtab->tp_first_diff;
diffout_T *dout = &dio->dio_diff;
bool notset = true; // block "*dp" not set yet
diffstyle_T diffstyle = DIFF_NONE;
if (!dio->dio_internal) {
fd = os_fopen(dout->dout_fname, "r");
if (fd == NULL) {
emsg(_("E98: Cannot read diff output"));
return;
}
}
while (true) {
diffhunk_T hunk = { 0 };
bool eof = dio->dio_internal
? extract_hunk_internal(dout, &hunk, &line_hunk_idx)
: extract_hunk(fd, &hunk, &diffstyle);
if (eof) {
break;
}
process_hunk(&dp, &dprev, idx_orig, idx_new, &hunk, &notset);
}
// for remaining diff blocks orig and new are equal
while (dp != NULL) {
if (notset) {
diff_copy_entry(dprev, dp, idx_orig, idx_new);
}
dprev = dp;
dp = dp->df_next;
notset = true;
}
if (fd != NULL) {
fclose(fd);
}
}
/// Copy an entry at "dp" from "idx_orig" to "idx_new".
///
/// @param dprev
/// @param dp
/// @param idx_orig
/// @param idx_new
static void diff_copy_entry(diff_T *dprev, diff_T *dp, int idx_orig, int idx_new)
{
linenr_T off;
if (dprev == NULL) {
off = 0;
} else {
off = (dprev->df_lnum[idx_orig] + dprev->df_count[idx_orig])
- (dprev->df_lnum[idx_new] + dprev->df_count[idx_new]);
}
dp->df_lnum[idx_new] = dp->df_lnum[idx_orig] - off;
dp->df_count[idx_new] = dp->df_count[idx_orig];
}
/// Clear the list of diffblocks for tab page "tp".
///
/// @param tp
void diff_clear(tabpage_T *tp)
FUNC_ATTR_NONNULL_ALL
{
diff_T *next_p;
for (diff_T *p = tp->tp_first_diff; p != NULL; p = next_p) {
next_p = p->df_next;
clear_diffblock(p);
}
tp->tp_first_diff = NULL;
}
/// Return true if the options are set to use diff linematch.
bool diff_linematch(diff_T *dp)
{
if (!(diff_flags & DIFF_LINEMATCH)) {
return false;
}
// are there more than three diff buffers?
int tsize = 0;
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
// for the rare case (bug?) that the count of a diff block is negative, do
// not run the algorithm because this will try to allocate a negative
// amount of space and crash
if (dp->df_count[i] < 0) {
return false;
}
tsize += dp->df_count[i];
}
}
// avoid allocating a huge array because it will lag
return tsize <= linematch_lines;
}
static int get_max_diff_length(const diff_T *dp)
{
int maxlength = 0;
for (int k = 0; k < DB_COUNT; k++) {
if (curtab->tp_diffbuf[k] != NULL) {
if (dp->df_count[k] > maxlength) {
maxlength = dp->df_count[k];
}
}
}
return maxlength;
}
/// Find the first diff block that includes the specified line. Also find the
/// next diff block that's not in the current chain of adjacent blocks that are
/// all touching each other directly.
static void find_top_diff_block(diff_T **thistopdiff, diff_T **next_adjacent_blocks, int fromidx,
int topline)
{
diff_T *topdiff = NULL;
diff_T *localtopdiff = NULL;
int topdiffchange = 0;
for (topdiff = curtab->tp_first_diff; topdiff != NULL; topdiff = topdiff->df_next) {
// set the top of the current overlapping diff block set as we
// iterate through all of the sets of overlapping diff blocks
if (!localtopdiff || topdiffchange) {
localtopdiff = topdiff;
topdiffchange = 0;
}
// check if the fromwin topline is matched by the current diff. if so,
// set it to the top of the diff block
if (topline >= topdiff->df_lnum[fromidx] && topline <=
(topdiff->df_lnum[fromidx] + topdiff->df_count[fromidx])) {
// this line is inside the current diff block, so we will save the
// top block of the set of blocks to refer to later
if ((*thistopdiff) == NULL) {
(*thistopdiff) = localtopdiff;
}
}
// check if the next set of overlapping diff blocks is next
if (!(topdiff->df_next && (topdiff->df_next->df_lnum[fromidx] ==
(topdiff->df_lnum[fromidx] + topdiff->df_count[fromidx])))) {
// mark that the next diff block is belongs to a different set of
// overlapping diff blocks
topdiffchange = 1;
// if we already have found that the line number is inside a diff block,
// set the marker of the next block and finish the iteration
if (*thistopdiff) {
(*next_adjacent_blocks) = topdiff->df_next;
break;
}
}
}
}
/// Calculates topline/topfill of a target diff window to fit the source diff window.
static void calculate_topfill_and_topline(const int fromidx, const int toidx, const
int from_topline, const int from_topfill, int *topfill,
linenr_T *topline)
{
// find the position from the top of the diff block, and the next diff
// block that's no longer adjacent to the current block. "Adjacency" means
// a chain of diff blocks that are directly touching each other, allowed by
// linematch and diff anchors.
diff_T *thistopdiff = NULL;
diff_T *next_adjacent_blocks = NULL;
int virtual_lines_passed = 0;
find_top_diff_block(&thistopdiff, &next_adjacent_blocks, fromidx, from_topline);
// count the virtual lines (either filler or concrete line) that have been
// passed in the source buffer. There could be multiple diff blocks if
// there are adjacent empty blocks (count == 0 at fromidx).
diff_T *curdif = thistopdiff;
while (curdif && (curdif->df_lnum[fromidx] + curdif->df_count[fromidx])
<= from_topline) {
virtual_lines_passed += get_max_diff_length(curdif);
curdif = curdif->df_next;
}
if (curdif != next_adjacent_blocks) {
virtual_lines_passed += from_topline - curdif->df_lnum[fromidx];
}
virtual_lines_passed -= from_topfill;
// clamp negative values in case from_topfill hasn't been updated yet and
// is larger than total virtual lines, which could happen when setting
// diffopt multiple times
if (virtual_lines_passed < 0) {
virtual_lines_passed = 0;
}
// move the same amount of virtual lines in the target buffer to find the
// cursor's line number
int curlinenum_to
= thistopdiff != NULL // this should not be null, but just for safety
? thistopdiff->df_lnum[toidx] : 1;
int virt_lines_left = virtual_lines_passed;
curdif = thistopdiff;
while (virt_lines_left > 0 && curdif != NULL && curdif != next_adjacent_blocks) {
curlinenum_to += MIN(virt_lines_left, curdif->df_count[toidx]);
virt_lines_left -= MIN(virt_lines_left, get_max_diff_length(curdif));
curdif = curdif->df_next;
}
// count the total number of virtual lines between the top diff block and
// the found line in the target buffer
int max_virt_lines = 0;
for (diff_T *dp = thistopdiff; dp != NULL; dp = dp->df_next) {
if (dp->df_lnum[toidx] + dp->df_count[toidx] <= curlinenum_to) {
max_virt_lines += get_max_diff_length(dp);
} else {
if (dp->df_lnum[toidx] <= curlinenum_to) {
max_virt_lines += curlinenum_to - dp->df_lnum[toidx];
}
break;
}
}
if (diff_flags & DIFF_FILLER) {
// should always be non-negative as max_virt_lines is larger
(*topfill) = max_virt_lines - virtual_lines_passed;
}
(*topline) = curlinenum_to;
}
// Apply results from the linematch algorithm and apply to 'dp' by splitting it into multiple
// adjacent diff blocks.
static void apply_linematch_results(diff_T *dp, size_t decisions_length, const int *decisions)
{
// get the start line number here in each diff buffer, and then increment
int line_numbers[DB_COUNT];
int outputmap[DB_COUNT];
size_t ndiffs = 0;
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
line_numbers[i] = dp->df_lnum[i];
dp->df_count[i] = 0;
// Keep track of the index of the diff buffer we are using here.
// We will use this to write the output of the algorithm to
// diff_T structs at the correct indexes
outputmap[ndiffs] = i;
ndiffs++;
}
}
// write the diffs starting with the current diff block
diff_T *dp_s = dp;
for (size_t i = 0; i < decisions_length; i++) {
// Don't allocate on first iter since we can reuse the initial diffblock
if (i != 0 && (decisions[i - 1] != decisions[i])) {
// create new sub diff blocks to segment the original diff block which we
// further divided by running the linematch algorithm
dp_s = diff_alloc_new(curtab, dp_s, dp_s->df_next);
dp_s->is_linematched = true;
for (int j = 0; j < DB_COUNT; j++) {
if (curtab->tp_diffbuf[j] != NULL) {
dp_s->df_lnum[j] = line_numbers[j];
dp_s->df_count[j] = 0;
}
}
}
for (size_t j = 0; j < ndiffs; j++) {
if (decisions[i] & (1 << j)) {
// will need to use the map here
dp_s->df_count[outputmap[j]]++;
line_numbers[outputmap[j]]++;
}
}
}
dp->is_linematched = true;
}
static void run_linematch_algorithm(diff_T *dp)
{
// define buffers for diff algorithm
mmfile_t diffbufs_mm[DB_COUNT];
const mmfile_t *diffbufs[DB_COUNT];
int diff_length[DB_COUNT];
size_t ndiffs = 0;
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] != NULL) {
if (dp->df_count[i] > 0) {
// write the contents of the entire buffer to
// diffbufs_mm[diffbuffers_count]
diff_write_buffer(curtab->tp_diffbuf[i], &diffbufs_mm[ndiffs],
dp->df_lnum[i], dp->df_lnum[i] + dp->df_count[i] - 1);
} else {
diffbufs_mm[ndiffs].size = 0;
diffbufs_mm[ndiffs].ptr = NULL;
}
diffbufs[ndiffs] = &diffbufs_mm[ndiffs];
// keep track of the length of this diff block to pass it to the linematch
// algorithm
diff_length[ndiffs] = dp->df_count[i];
// increment the amount of diff buffers we are passing to the algorithm
ndiffs++;
}
}
// we will get the output of the linematch algorithm in the format of an array
// of integers (*decisions) and the length of that array (decisions_length)
int *decisions = NULL;
const bool iwhite = (diff_flags & (DIFF_IWHITEALL | DIFF_IWHITE)) > 0;
size_t decisions_length = linematch_nbuffers(diffbufs, diff_length, ndiffs, &decisions, iwhite);
for (size_t i = 0; i < ndiffs; i++) {
XFREE_CLEAR(diffbufs_mm[i].ptr);
}
apply_linematch_results(dp, decisions_length, decisions);
xfree(decisions);
}
/// Check diff status for line "lnum" in buffer "buf":
///
/// Returns > 0 for inserting that many filler lines above it (never happens
/// when 'diffopt' doesn't contain "filler"). Otherwise returns 0.
///
/// "linestatus" (can be NULL) will be set to:
/// 0 for nothing special.
/// -1 for a line that should be highlighted as changed.
/// -2 for a line that should be highlighted as added/deleted.
///
/// This should only be used for windows where 'diff' is set.
///
/// Note that it's possible for a changed/added/deleted line to also have filler
/// lines above it. This happens when using linematch or using diff anchors (at
/// the anchored lines).
///
/// @param wp
/// @param lnum
/// @param[out] linestatus
///
/// @return diff status.
int diff_check_with_linestatus(win_T *wp, linenr_T lnum, int *linestatus)
{
buf_T *buf = wp->w_buffer;
if (linestatus != NULL) {
*linestatus = 0;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
// no diffs at all
if ((curtab->tp_first_diff == NULL) || !wp->w_p_diff) {
return 0;
}
// safety check: "lnum" must be a buffer line
if ((lnum < 1) || (lnum > buf->b_ml.ml_line_count + 1)) {
return 0;
}
int idx = diff_buf_idx(buf, curtab); // index in tp_diffbuf[] for this buffer
if (idx == DB_COUNT) {
// no diffs for buffer "buf"
return 0;
}
// A closed fold never has filler lines.
if (hasFolding(wp, lnum, NULL, NULL) || decor_conceal_line(wp, lnum - 1, false)) {
return 0;
}
// search for a change that includes "lnum" in the list of diffblocks.
diff_T *dp;
for (dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
if (lnum <= dp->df_lnum[idx] + dp->df_count[idx]) {
break;
}
}
if ((dp == NULL) || (lnum < dp->df_lnum[idx])) {
return 0;
}
// Don't run linematch when lnum is offscreen.
// Useful for scrollbind calculations which need to count all the filler lines
// above the screen.
if (lnum >= wp->w_topline && lnum < wp->w_botline
&& !dp->is_linematched && diff_linematch(dp)
&& diff_check_sanity(curtab, dp)) {
run_linematch_algorithm(dp);
}
// Insert filler lines above the line just below the change. Will return 0
// when this buf had the max count.
int num_fill = 0;
while (lnum == dp->df_lnum[idx] + dp->df_count[idx]) {
// Only calculate fill lines if 'diffopt' contains "filler". Otherwise
// returns 0 filler lines.
if (diff_flags & DIFF_FILLER) {
int maxcount = get_max_diff_length(dp);
num_fill += maxcount - dp->df_count[idx];
}
// If there are adjacent blocks (e.g. linematch or anchor), loop
// through them. It's possible for multiple adjacent blocks to
// contribute to filler lines.
// This also helps us find the last diff block in the list of adjacent
// blocks which is necessary when it is a change/inserted line right
// after added lines.
if (dp->df_next != NULL
&& lnum >= dp->df_next->df_lnum[idx]
&& lnum <= dp->df_next->df_lnum[idx] + dp->df_next->df_count[idx]) {
dp = dp->df_next;
} else {
break;
}
}
if (lnum < dp->df_lnum[idx] + dp->df_count[idx]) {
bool zero = false;
// Changed or inserted line. If the other buffers have a count of
// zero, the lines were inserted. If the other buffers have the same
// count, check if the lines are identical.
bool cmp = false;
for (int i = 0; i < DB_COUNT; i++) {
if ((i != idx) && (curtab->tp_diffbuf[i] != NULL)) {
if (dp->df_count[i] == 0) {
zero = true;
} else {
if (dp->df_count[i] != dp->df_count[idx]) {
if (linestatus) {
*linestatus = -1; // nr of lines changed.
}
return num_fill;
}
cmp = true;
}
}
}
if (cmp) {
// Compare all lines. If they are equal the lines were inserted
// in some buffers, deleted in others, but not changed.
for (int i = 0; i < DB_COUNT; i++) {
if ((i != idx)
&& (curtab->tp_diffbuf[i] != NULL)
&& (dp->df_count[i] != 0)) {
if (!diff_equal_entry(dp, idx, i)) {
if (linestatus) {
*linestatus = -1;
}
return num_fill;
}
}
}
}
// If there is no buffer with zero lines then there is no difference
// any longer. Happens when making a change (or undo) that removes
// the difference. Can't remove the entry here, we might be halfway
// through updating the window. Just report the text as unchanged.
// Other windows might still show the change though.
if (!zero) {
return num_fill;
}
if (linestatus) {
*linestatus = -2;
}
return num_fill;
}
return num_fill;
}
/// See diff_check_with_linestatus
int diff_check_fill(win_T *wp, linenr_T lnum)
{
// be quick when there are no filler lines
if (!(diff_flags & DIFF_FILLER)) {
return 0;
}
int n = diff_check_with_linestatus(wp, lnum, NULL);
return MAX(n, 0);
}
/// Compare two entries in diff "dp" and return true if they are equal.
///
/// @param dp diff
/// @param idx1 first entry in diff "dp"
/// @param idx2 second entry in diff "dp"
///
/// @return true if two entries are equal.
static bool diff_equal_entry(diff_T *dp, int idx1, int idx2)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ARG(1)
{
if (dp->df_count[idx1] != dp->df_count[idx2]) {
return false;
}
if (diff_check_sanity(curtab, dp) == FAIL) {
return false;
}
for (int i = 0; i < dp->df_count[idx1]; i++) {
char *line = xstrdup(ml_get_buf(curtab->tp_diffbuf[idx1], dp->df_lnum[idx1] + i));
int cmp = diff_cmp(line, ml_get_buf(curtab->tp_diffbuf[idx2], dp->df_lnum[idx2] + i));
xfree(line);
if (cmp != 0) {
return false;
}
}
return true;
}
// Compare the characters at "p1" and "p2". If they are equal (possibly
// ignoring case) return true and set "len" to the number of bytes.
static bool diff_equal_char(const char *const p1, const char *const p2, int *const len)
{
const int l = utfc_ptr2len(p1);
if (l != utfc_ptr2len(p2)) {
return false;
}
if (l > 1) {
if (strncmp(p1, p2, (size_t)l) != 0
&& (!(diff_flags & DIFF_ICASE)
|| utf_fold(utf_ptr2char(p1)) != utf_fold(utf_ptr2char(p2)))) {
return false;
}
*len = l;
} else {
if ((*p1 != *p2)
&& (!(diff_flags & DIFF_ICASE)
|| TOLOWER_LOC((uint8_t)(*p1)) != TOLOWER_LOC((uint8_t)(*p2)))) {
return false;
}
*len = 1;
}
return true;
}
/// Compare strings "s1" and "s2" according to 'diffopt'.
/// Return non-zero when they are different.
///
/// @param s1 The first string
/// @param s2 The second string
///
/// @return on-zero if the two strings are different.
static int diff_cmp(char *s1, char *s2)
{
if ((diff_flags & DIFF_IBLANK)
&& (*skipwhite(s1) == NUL || *skipwhite(s2) == NUL)) {
return 0;
}
if ((diff_flags & (DIFF_ICASE | ALL_WHITE_DIFF)) == 0) {
return strcmp(s1, s2);
}
if ((diff_flags & DIFF_ICASE) && !(diff_flags & ALL_WHITE_DIFF)) {
return mb_stricmp(s1, s2);
}
char *p1 = s1;
char *p2 = s2;
// Ignore white space changes and possibly ignore case.
while (*p1 != NUL && *p2 != NUL) {
if (((diff_flags & DIFF_IWHITE)
&& ascii_iswhite(*p1) && ascii_iswhite(*p2))
|| ((diff_flags & DIFF_IWHITEALL)
&& (ascii_iswhite(*p1) || ascii_iswhite(*p2)))) {
p1 = skipwhite(p1);
p2 = skipwhite(p2);
} else {
int l;
if (!diff_equal_char(p1, p2, &l)) {
break;
}
p1 += l;
p2 += l;
}
}
// Ignore trailing white space.
p1 = skipwhite(p1);
p2 = skipwhite(p2);
if ((*p1 != NUL) || (*p2 != NUL)) {
return 1;
}
return 0;
}
/// Set the topline of "towin" to match the position in "fromwin", so that they
/// show the same diff'ed lines.
///
/// @param fromwin
/// @param towin
void diff_set_topline(win_T *fromwin, win_T *towin)
{
buf_T *frombuf = fromwin->w_buffer;
int fromidx = diff_buf_idx(frombuf, curtab);
if (fromidx == DB_COUNT) {
// safety check
return;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
linenr_T lnum = fromwin->w_topline;
towin->w_topfill = 0;
// search for a change that includes "lnum" in the list of diffblocks.
diff_T *dp;
for (dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
if (lnum <= dp->df_lnum[fromidx] + dp->df_count[fromidx]) {
break;
}
}
if (dp == NULL) {
// After last change, compute topline relative to end of file; no
// filler lines.
towin->w_topline = towin->w_buffer->b_ml.ml_line_count
- (frombuf->b_ml.ml_line_count - lnum);
} else {
// Find index for "towin".
int toidx = diff_buf_idx(towin->w_buffer, curtab);
if (toidx == DB_COUNT) {
// safety check
return;
}
towin->w_topline = lnum + (dp->df_lnum[toidx] - dp->df_lnum[fromidx]);
if (lnum >= dp->df_lnum[fromidx]) {
calculate_topfill_and_topline(fromidx, toidx,
fromwin->w_topline, fromwin->w_topfill,
&towin->w_topfill, &towin->w_topline);
}
}
// safety check (if diff info gets outdated strange things may happen)
towin->w_botfill = false;
if (towin->w_topline > towin->w_buffer->b_ml.ml_line_count) {
towin->w_topline = towin->w_buffer->b_ml.ml_line_count;
towin->w_botfill = true;
}
if (towin->w_topline < 1) {
towin->w_topline = 1;
towin->w_topfill = 0;
}
// When w_topline changes need to recompute w_botline and cursor position
invalidate_botline(towin);
changed_line_abv_curs_win(towin);
check_topfill(towin, false);
hasFolding(towin, towin->w_topline, &towin->w_topline, NULL);
}
/// Parse the diff anchors. If "check_only" is set, will only make sure the
/// syntax is correct.
static int parse_diffanchors(bool check_only, buf_T *buf, linenr_T *anchors, int *num_anchors)
{
int i;
char *dia = (*buf->b_p_dia == NUL) ? p_dia : buf->b_p_dia;
buf_T *orig_curbuf = curbuf;
win_T *orig_curwin = curwin;
win_T *bufwin = NULL;
if (check_only) {
bufwin = curwin;
} else {
// Find the first window tied to this buffer and ignore the rest. Will
// only matter for window-specific addresses like `.` or `''`.
for (bufwin = firstwin; bufwin != NULL; bufwin = bufwin->w_next) {
if (bufwin->w_buffer == buf && bufwin->w_p_diff) {
break;
}
}
if (bufwin == NULL && *dia != NUL) {
// The buffer is hidden. Currently this is not supported due to the
// edge cases of needing to decide if an address is window-specific
// or not. We could add more checks in the future so we can detect
// whether an address relies on curwin to make this more fleixble.
emsg(_(e_diff_anchors_with_hidden_windows));
return FAIL;
}
}
for (i = 0; i < MAX_DIFF_ANCHORS && *dia != NUL; i++) {
if (*dia == ',') { // don't allow empty values
return FAIL;
}
curbuf = buf;
curwin = bufwin;
const char *errormsg = NULL;
linenr_T lnum = get_address(NULL, &dia, ADDR_LINES, check_only, true, false, 1, &errormsg);
curbuf = orig_curbuf;
curwin = orig_curwin;
if (errormsg != NULL) {
emsg(errormsg);
}
if (dia == NULL) { // error detected
return FAIL;
}
if (*dia != ',' && *dia != NUL) {
return FAIL;
}
if (!check_only
&& (lnum == MAXLNUM || lnum <= 0 || lnum > buf->b_ml.ml_line_count + 1)) {
emsg(_(e_invrange));
return FAIL;
}
if (anchors != NULL) {
anchors[i] = lnum;
}
if (*dia == ',') {
dia++;
}
}
if (i == MAX_DIFF_ANCHORS && *dia != NUL) {
semsg(_(e_cannot_have_more_than_nr_diff_anchors), MAX_DIFF_ANCHORS);
return FAIL;
}
if (num_anchors != NULL) {
*num_anchors = i;
}
return OK;
}
/// This is called when 'diffanchors' is changed.
int diffanchors_changed(bool buflocal)
{
int result = parse_diffanchors(true, curbuf, NULL, NULL);
if (result == OK && (diff_flags & DIFF_ANCHOR)) {
FOR_ALL_TABS(tp) {
if (!buflocal) {
tp->tp_diff_invalid = true;
} else {
for (int idx = 0; idx < DB_COUNT; idx++) {
if (tp->tp_diffbuf[idx] == curbuf) {
tp->tp_diff_invalid = true;
break;
}
}
}
}
}
return result;
}
/// This is called when 'diffopt' is changed.
///
/// @return
int diffopt_changed(void)
{
int diff_context_new = 6;
int linematch_lines_new = 0;
int diff_flags_new = 0;
int diff_foldcolumn_new = 2;
int diff_algorithm_new = 0;
int diff_indent_heuristic = 0;
char *p = p_dip;
while (*p != NUL) {
// Note: Keep this in sync with opt_dip_values.
if (strncmp(p, "filler", 6) == 0) {
p += 6;
diff_flags_new |= DIFF_FILLER;
} else if (strncmp(p, "anchor", 6) == 0) {
p += 6;
diff_flags_new |= DIFF_ANCHOR;
} else if ((strncmp(p, "context:", 8) == 0) && ascii_isdigit(p[8])) {
p += 8;
diff_context_new = getdigits_int(&p, false, diff_context_new);
} else if (strncmp(p, "iblank", 6) == 0) {
p += 6;
diff_flags_new |= DIFF_IBLANK;
} else if (strncmp(p, "icase", 5) == 0) {
p += 5;
diff_flags_new |= DIFF_ICASE;
} else if (strncmp(p, "iwhiteall", 9) == 0) {
p += 9;
diff_flags_new |= DIFF_IWHITEALL;
} else if (strncmp(p, "iwhiteeol", 9) == 0) {
p += 9;
diff_flags_new |= DIFF_IWHITEEOL;
} else if (strncmp(p, "iwhite", 6) == 0) {
p += 6;
diff_flags_new |= DIFF_IWHITE;
} else if (strncmp(p, "horizontal", 10) == 0) {
p += 10;
diff_flags_new |= DIFF_HORIZONTAL;
} else if (strncmp(p, "vertical", 8) == 0) {
p += 8;
diff_flags_new |= DIFF_VERTICAL;
} else if ((strncmp(p, "foldcolumn:", 11) == 0) && ascii_isdigit(p[11])) {
p += 11;
diff_foldcolumn_new = getdigits_int(&p, false, diff_foldcolumn_new);
} else if (strncmp(p, "hiddenoff", 9) == 0) {
p += 9;
diff_flags_new |= DIFF_HIDDEN_OFF;
} else if (strncmp(p, "closeoff", 8) == 0) {
p += 8;
diff_flags_new |= DIFF_CLOSE_OFF;
} else if (strncmp(p, "followwrap", 10) == 0) {
p += 10;
diff_flags_new |= DIFF_FOLLOWWRAP;
} else if (strncmp(p, "indent-heuristic", 16) == 0) {
p += 16;
diff_indent_heuristic = XDF_INDENT_HEURISTIC;
} else if (strncmp(p, "internal", 8) == 0) {
p += 8;
diff_flags_new |= DIFF_INTERNAL;
} else if (strncmp(p, "algorithm:", 10) == 0) {
// Note: Keep this in sync with opt_dip_algorithm_values.
p += 10;
if (strncmp(p, "myers", 5) == 0) {
p += 5;
diff_algorithm_new = 0;
} else if (strncmp(p, "minimal", 7) == 0) {
p += 7;
diff_algorithm_new = XDF_NEED_MINIMAL;
} else if (strncmp(p, "patience", 8) == 0) {
p += 8;
diff_algorithm_new = XDF_PATIENCE_DIFF;
} else if (strncmp(p, "histogram", 9) == 0) {
p += 9;
diff_algorithm_new = XDF_HISTOGRAM_DIFF;
} else {
return FAIL;
}
} else if (strncmp(p, "inline:", 7) == 0) {
// Note: Keep this in sync with opt_dip_inline_values.
p += 7;
if (strncmp(p, "none", 4) == 0) {
p += 4;
diff_flags_new &= ~(ALL_INLINE);
diff_flags_new |= DIFF_INLINE_NONE;
} else if (strncmp(p, "simple", 6) == 0) {
p += 6;
diff_flags_new &= ~(ALL_INLINE);
diff_flags_new |= DIFF_INLINE_SIMPLE;
} else if (strncmp(p, "char", 4) == 0) {
p += 4;
diff_flags_new &= ~(ALL_INLINE);
diff_flags_new |= DIFF_INLINE_CHAR;
} else if (strncmp(p, "word", 4) == 0) {
p += 4;
diff_flags_new &= ~(ALL_INLINE);
diff_flags_new |= DIFF_INLINE_WORD;
} else {
return FAIL;
}
} else if ((strncmp(p, "linematch:", 10) == 0) && ascii_isdigit(p[10])) {
p += 10;
linematch_lines_new = getdigits_int(&p, false, linematch_lines_new);
diff_flags_new |= DIFF_LINEMATCH;
// linematch does not make sense without filler set
diff_flags_new |= DIFF_FILLER;
}
if ((*p != ',') && (*p != NUL)) {
return FAIL;
}
if (*p == ',') {
p++;
}
}
diff_algorithm_new |= diff_indent_heuristic;
// Can't have both "horizontal" and "vertical".
if ((diff_flags_new & DIFF_HORIZONTAL) && (diff_flags_new & DIFF_VERTICAL)) {
return FAIL;
}
// If flags were added or removed, or the algorithm was changed, need to
// update the diff.
if (diff_flags != diff_flags_new || diff_algorithm != diff_algorithm_new) {
FOR_ALL_TABS(tp) {
tp->tp_diff_invalid = true;
}
}
diff_flags = diff_flags_new;
diff_context = diff_context_new == 0 ? 1 : diff_context_new;
linematch_lines = linematch_lines_new;
diff_foldcolumn = diff_foldcolumn_new;
diff_algorithm = diff_algorithm_new;
diff_redraw(true);
// recompute the scroll binding with the new option value, may
// remove or add filler lines
check_scrollbind(0, 0);
return OK;
}
/// Check that "diffopt" contains "horizontal".
bool diffopt_horizontal(void)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
{
return (diff_flags & DIFF_HORIZONTAL) != 0;
}
// Return true if 'diffopt' contains "hiddenoff".
bool diffopt_hiddenoff(void)
FUNC_ATTR_PURE
{
return (diff_flags & DIFF_HIDDEN_OFF) != 0;
}
// Return true if 'diffopt' contains "closeoff".
bool diffopt_closeoff(void)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
{
return (diff_flags & DIFF_CLOSE_OFF) != 0;
}
// Return true if 'diffopt' contains "filler".
bool diffopt_filler(void)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
{
return (diff_flags & DIFF_FILLER) != 0;
}
/// Called when a line has been updated. Used for updating inline diff in Insert
/// mode without waiting for global diff update later.
void diff_update_line(linenr_T lnum)
{
if (!(diff_flags & ALL_INLINE_DIFF)) {
// We only care if we are doing inline-diff where we cache the diff results
return;
}
int idx = diff_buf_idx(curbuf, curtab);
if (idx == DB_COUNT) {
return;
}
diff_T *dp;
FOR_ALL_DIFFBLOCKS_IN_TAB(curtab, dp) {
if (lnum <= dp->df_lnum[idx] + dp->df_count[idx]) {
break;
}
}
// clear the inline change cache as it's invalid
if (dp != NULL) {
dp->has_changes = false;
dp->df_changes.ga_len = 0;
}
}
/// used for simple inline diff algorithm
static diffline_change_T simple_diffline_change;
/// Parse a diffline struct and returns the [start,end] byte offsets
///
/// Returns true if this change was added, no other buffer has it.
bool diff_change_parse(diffline_T *diffline, diffline_change_T *change, int *change_start,
int *change_end)
{
if (change->dc_start_lnum_off[diffline->bufidx] < diffline->lineoff) {
*change_start = 0;
} else {
*change_start = change->dc_start[diffline->bufidx];
}
if (change->dc_end_lnum_off[diffline->bufidx] > diffline->lineoff) {
*change_end = INT_MAX;
} else {
*change_end = change->dc_end[diffline->bufidx];
}
if (change == &simple_diffline_change) {
// This is what we returned from simple inline diff. We always consider
// the range to be changed, rather than added for now.
return false;
}
// Find out whether this is an addition. Note that for multi buffer diff,
// to tell whether lines are additions we check whether all the other diff
// lines are identical (in diff_check_with_linestatus). If so, we mark them
// as add. We don't do that for inline diff here for simplicity.
for (int i = 0; i < DB_COUNT; i++) {
if (i == diffline->bufidx) {
continue;
}
if (change->dc_start[i] != change->dc_end[i]
|| change->dc_end_lnum_off[i] != change->dc_start_lnum_off[i]) {
return false;
}
}
return true;
}
/// Find the difference within a changed line and returns [startp,endp] byte
/// positions. Performs a simple algorithm by finding a single range in the
/// middle.
///
/// If diffopt has DIFF_INLINE_NONE set, then this will only calculate the return
/// value (added or changed), but startp/endp will not be calculated.
///
/// @param wp window whose current buffer to check
/// @param lnum line number to check within the buffer
/// @param startp first char of the change
/// @param endp last char of the change
///
/// @return true if the line was added, no other buffer has it.
static bool diff_find_change_simple(win_T *wp, linenr_T lnum, const diff_T *dp, int idx,
int *startp, int *endp)
FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
{
char *line_org;
if (diff_flags & DIFF_INLINE_NONE) {
// We only care about the return value, not the actual string comparisons.
line_org = NULL;
} else {
// Make a copy of the line, the next ml_get() will invalidate it.
line_org = xstrdup(ml_get_buf(wp->w_buffer, lnum));
}
int si_org;
int si_new;
int ei_org;
int ei_new;
bool added = true;
linenr_T off = lnum - dp->df_lnum[idx];
for (int i = 0; i < DB_COUNT; i++) {
if ((curtab->tp_diffbuf[i] != NULL) && (i != idx)) {
// Skip lines that are not in the other change (filler lines).
if (off >= dp->df_count[i]) {
continue;
}
added = false;
if (diff_flags & DIFF_INLINE_NONE) {
break; // early terminate as we only care about the return value
}
char *line_new = ml_get_buf(curtab->tp_diffbuf[i], dp->df_lnum[i] + off);
// Search for start of difference
si_org = si_new = 0;
while (line_org[si_org] != NUL) {
if (((diff_flags & DIFF_IWHITE)
&& ascii_iswhite(line_org[si_org])
&& ascii_iswhite(line_new[si_new]))
|| ((diff_flags & DIFF_IWHITEALL)
&& (ascii_iswhite(line_org[si_org])
|| ascii_iswhite(line_new[si_new])))) {
si_org = (int)(skipwhite(line_org + si_org) - line_org);
si_new = (int)(skipwhite(line_new + si_new) - line_new);
} else {
int l;
if (!diff_equal_char(line_org + si_org, line_new + si_new, &l)) {
break;
}
si_org += l;
si_new += l;
}
}
// Move back to first byte of character in both lines (may
// have "nn^" in line_org and "n^ in line_new).
si_org -= utf_head_off(line_org, line_org + si_org);
si_new -= utf_head_off(line_new, line_new + si_new);
*startp = MIN(*startp, si_org);
// Search for end of difference, if any.
if ((line_org[si_org] != NUL) || (line_new[si_new] != NUL)) {
ei_org = (int)strlen(line_org);
ei_new = (int)strlen(line_new);
while (ei_org >= *startp
&& ei_new >= si_new
&& ei_org >= 0
&& ei_new >= 0) {
if (((diff_flags & DIFF_IWHITE)
&& ascii_iswhite(line_org[ei_org])
&& ascii_iswhite(line_new[ei_new]))
|| ((diff_flags & DIFF_IWHITEALL)
&& (ascii_iswhite(line_org[ei_org])
|| ascii_iswhite(line_new[ei_new])))) {
while (ei_org >= *startp && ascii_iswhite(line_org[ei_org])) {
ei_org--;
}
while (ei_new >= si_new && ascii_iswhite(line_new[ei_new])) {
ei_new--;
}
} else {
const char *p1 = line_org + ei_org;
const char *p2 = line_new + ei_new;
p1 -= utf_head_off(line_org, p1);
p2 -= utf_head_off(line_new, p2);
int l;
if (!diff_equal_char(p1, p2, &l)) {
break;
}
ei_org -= l;
ei_new -= l;
}
}
*endp = MAX(*endp, ei_org);
}
}
}
xfree(line_org);
return added;
}
/// Mapping used for mapping from temporary mmfile created for inline diff back
/// to original buffer's line/col.
typedef struct {
colnr_T byte_start;
colnr_T num_bytes;
int lineoff;
} linemap_entry_T;
/// Refine inline character-wise diff blocks to create a more human readable
/// highlight. Otherwise a naive diff under existing algorithms tends to create
/// a messy output with lots of small gaps.
/// It does this by merging adjacent long diff blocks if they are only separated
/// by a couple characters.
/// These are done by heuristics and can be further tuned.
static void diff_refine_inline_char_highlight(diff_T *dp_orig, garray_T *linemap, int idx1)
{
// Perform multiple passes so that newly merged blocks will now be long
// enough which may cause other previously unmerged gaps to be merged as
// well.
int pass = 1;
do {
bool has_unmerged_gaps = false;
bool has_merged_gaps = false;
diff_T *dp = dp_orig;
while (dp != NULL && dp->df_next != NULL) {
// Only use first buffer to calculate the gap because the gap is
// unchanged text, which would be the same in all buffers.
if (dp->df_lnum[idx1] + dp->df_count[idx1] - 1 >= linemap[idx1].ga_len
|| dp->df_next->df_lnum[idx1] - 1 >= linemap[idx1].ga_len) {
dp = dp->df_next;
continue;
}
// If the gap occurs over different lines, don't consider it
linemap_entry_T *entry1 =
&((linemap_entry_T *)linemap[idx1].ga_data)[dp->df_lnum[idx1]
+ dp->df_count[idx1] - 1];
linemap_entry_T *entry2 =
&((linemap_entry_T *)linemap[idx1].ga_data)[dp->df_next->df_lnum[idx1] - 1];
if (entry1->lineoff != entry2->lineoff) {
dp = dp->df_next;
continue;
}
linenr_T gap = dp->df_next->df_lnum[idx1] - (dp->df_lnum[idx1] + dp->df_count[idx1]);
if (gap <= 3) {
linenr_T max_df_count = 0;
for (int i = 0; i < DB_COUNT; i++) {
max_df_count = MAX(max_df_count, dp->df_count[i] + dp->df_next->df_count[i]);
}
if (max_df_count >= gap * 4) {
// Merge current block with the next one. Don't advance the
// pointer so we try the same merged block against the next
// one.
for (int i = 0; i < DB_COUNT; i++) {
dp->df_count[i] = dp->df_next->df_lnum[i]
+ dp->df_next->df_count[i] - dp->df_lnum[i];
}
diff_T *dp_next = dp->df_next;
dp->df_next = dp_next->df_next;
clear_diffblock(dp_next);
has_merged_gaps = true;
continue;
} else {
has_unmerged_gaps = true;
}
}
dp = dp->df_next;
}
if (!has_unmerged_gaps || !has_merged_gaps) {
break;
}
} while (pass++ < 4); // use limited number of passes to avoid excessive looping
}
/// Find the inline difference within a diff block among different buffers. Do
/// this by splitting each block's content into characters or words, and then
/// use internal xdiff to calculate the per-character/word diff. The result is
/// stored in dp instead of returned by the function.
static void diff_find_change_inline_diff(diff_T *dp)
{
const int save_diff_algorithm = diff_algorithm;
diffio_T dio = { 0 };
ga_init(&dio.dio_diff.dout_ga, sizeof(diffhunk_T), 1000);
// inline diff only supports internal algo
dio.dio_internal = true;
// always use indent-heuristics to slide diff splits along
// whitespace
diff_algorithm |= XDF_INDENT_HEURISTIC;
// diff_read() has an implicit dependency on curtab->tp_first_diff
diff_T *orig_diff = curtab->tp_first_diff;
curtab->tp_first_diff = NULL;
// diff_read() also uses curtab->tp_diffbuf to determine what's an active
// buffer
buf_T *(orig_diffbuf[DB_COUNT]);
memcpy(orig_diffbuf, curtab->tp_diffbuf, sizeof(orig_diffbuf));
garray_T linemap[DB_COUNT];
garray_T file1_str;
garray_T file2_str;
// Buffers to populate mmfile 1/2 that would be passed to xdiff as memory
// files. Use a grow array as it is not obvious how much exact space we
// need.
ga_init(&file1_str, 1, 1024);
ga_init(&file2_str, 1, 1024);
// Line map to map from generated mmfiles' line numbers back to original
// diff blocks' locations. Need this even for char diff because not all
// characters are 1-byte long / ASCII.
for (int i = 0; i < DB_COUNT; i++) {
ga_init(&linemap[i], sizeof(linemap_entry_T), 128);
}
int file1_idx = -1;
for (int i = 0; i < DB_COUNT; i++) {
dio.dio_diff.dout_ga.ga_len = 0;
buf_T *buf = curtab->tp_diffbuf[i];
if (buf == NULL || buf->b_ml.ml_mfp == NULL) {
continue; // skip buffer that isn't loaded
}
if (dp->df_count[i] == 0) {
// skip buffers that don't have any texts in this block so we don't
// end up marking the entire block as modified in multi-buffer diff
curtab->tp_diffbuf[i] = NULL;
continue;
}
if (file1_idx == -1) {
file1_idx = i;
}
garray_T *curstr = (file1_idx != i) ? &file2_str : &file1_str;
linenr_T numlines = 0;
curstr->ga_len = 0;
// Split each line into chars/words and populate fake file buffer as
// newline-delimited tokens as that's what xdiff requires.
for (int off = 0; off < dp->df_count[i]; off++) {
char *curline = ml_get_buf(curtab->tp_diffbuf[i], dp->df_lnum[i] + off);
bool in_keyword = false;
// iwhiteeol support vars
bool last_white = false;
int eol_ga_len = -1;
int eol_linemap_len = -1;
int eol_numlines = -1;
char *s = curline;
while (*s != NUL) {
bool new_in_keyword = false;
if (diff_flags & DIFF_INLINE_WORD) {
// Always use the first buffer's 'iskeyword' to have a
// consistent diff.
// For multibyte chars, only treat alphanumeric chars
// (class 2) as "word", as other classes such as emojis and
// CJK ideographs do not usually benefit from word diff as
// Vim doesn't have a good way to segment them.
new_in_keyword = (mb_get_class_tab(s, curtab->tp_diffbuf[file1_idx]->b_chartab) == 2);
}
if (in_keyword && !new_in_keyword) {
ga_append(curstr, NL);
numlines++;
}
if (ascii_iswhite(*s)) {
if (diff_flags & DIFF_IWHITEALL) {
in_keyword = false;
s = skipwhite(s);
continue;
} else if ((diff_flags & DIFF_IWHITEEOL) || (diff_flags & DIFF_IWHITE)) {
if (!last_white) {
eol_ga_len = curstr->ga_len;
eol_linemap_len = linemap[i].ga_len;
eol_numlines = numlines;
last_white = true;
}
}
} else {
if ((diff_flags & DIFF_IWHITEEOL) || (diff_flags & DIFF_IWHITE)) {
last_white = false;
eol_ga_len = -1;
eol_linemap_len = -1;
eol_numlines = -1;
}
}
int char_len = 1;
if (*s == NL) {
// NL is internal substitute for NUL
ga_append(curstr, NUL);
} else {
char_len = utfc_ptr2len(s);
if (ascii_iswhite(*s) && (diff_flags & DIFF_IWHITE)) {
// Treat the entire white space span as a single char.
char_len = (int)(skipwhite(s) - s);
}
if (diff_flags & DIFF_ICASE) {
// xdiff doesn't support ignoring case, fold-case the text manually.
int c = utf_ptr2char(s);
int c_len = utf_char2len(c);
c = utf_fold(c);
char cbuf[MB_MAXBYTES + 1];
int c_fold_len = utf_char2bytes(c, cbuf);
ga_concat_len(curstr, cbuf, (size_t)c_fold_len);
if (char_len > c_len) {
// There may be remaining composing characters. Write those back in.
// Composing characters don't need case folding.
ga_concat_len(curstr, s + c_len, (size_t)(char_len - c_len));
}
} else {
ga_concat_len(curstr, s, (size_t)char_len);
}
}
if (!new_in_keyword) {
ga_append(curstr, NL);
numlines++;
}
if (!new_in_keyword || (new_in_keyword && !in_keyword)) {
// create a new mapping entry from the xdiff mmfile back to
// original line/col.
linemap_entry_T linemap_entry = {
.lineoff = off,
.byte_start = (colnr_T)(s - curline),
.num_bytes = char_len,
};
GA_APPEND(linemap_entry_T, &linemap[i], linemap_entry);
} else {
// Still inside a keyword. Just increment byte count but
// don't make a new entry.
// linemap always has at least one entry here
((linemap_entry_T *)linemap[i].ga_data)[linemap[i].ga_len - 1].num_bytes += char_len;
}
in_keyword = new_in_keyword;
s += char_len;
}
if (in_keyword) {
ga_append(curstr, NL);
numlines++;
}
if ((diff_flags & DIFF_IWHITEEOL) || (diff_flags & DIFF_IWHITE)) {
// Need to trim trailing whitespace. Do this simply by
// resetting arrays back to before we encountered them.
if (eol_ga_len != -1) {
curstr->ga_len = eol_ga_len;
linemap[i].ga_len = eol_linemap_len;
numlines = eol_numlines;
}
}
if (!(diff_flags & DIFF_IWHITEALL)) {
// Add an empty line token mapped to the end-of-line in the
// original file. This helps diff newline differences among
// files, which will be visualized when using 'list' as the eol
// listchar will be highlighted.
ga_append(curstr, NL);
numlines++;
linemap_entry_T linemap_entry = {
.lineoff = off,
.byte_start = (colnr_T)(s - curline),
.num_bytes = sizeof(NL),
};
GA_APPEND(linemap_entry_T, &linemap[i], linemap_entry);
}
}
if (file1_idx != i) {
dio.dio_new.din_mmfile.ptr = (char *)curstr->ga_data;
dio.dio_new.din_mmfile.size = curstr->ga_len;
} else {
dio.dio_orig.din_mmfile.ptr = (char *)curstr->ga_data;
dio.dio_orig.din_mmfile.size = curstr->ga_len;
}
if (file1_idx != i) {
// Perform diff with first file and read the results
int diff_status = diff_file_internal(&dio);
if (diff_status == FAIL) {
goto done;
}
diff_read(0, i, &dio);
clear_diffout(&dio.dio_diff);
}
}
diff_T *new_diff = curtab->tp_first_diff;
if (diff_flags & DIFF_INLINE_CHAR && file1_idx != -1) {
diff_refine_inline_char_highlight(new_diff, linemap, file1_idx);
}
// After the diff, use the linemap to obtain the original line/col of the
// changes and cache them in dp.
dp->df_changes.ga_len = 0; // this should already be zero
for (; new_diff != NULL; new_diff = new_diff->df_next) {
diffline_change_T change = { 0 };
for (int i = 0; i < DB_COUNT; i++) {
if (new_diff->df_lnum[i] <= 0) { // should never be < 0. Checking just for safety
continue;
}
linenr_T diff_lnum = new_diff->df_lnum[i] - 1; // use zero-index
linenr_T diff_lnum_end = diff_lnum + new_diff->df_count[i];
if (diff_lnum >= linemap[i].ga_len) {
change.dc_start[i] = MAXCOL;
change.dc_start_lnum_off[i] = INT_MAX;
} else {
change.dc_start[i] = ((linemap_entry_T *)linemap[i].ga_data)[diff_lnum].byte_start;
change.dc_start_lnum_off[i] = ((linemap_entry_T *)linemap[i].ga_data)[diff_lnum].lineoff;
}
if (diff_lnum == diff_lnum_end) {
change.dc_end[i] = change.dc_start[i];
change.dc_end_lnum_off[i] = change.dc_start_lnum_off[i];
} else if (diff_lnum_end - 1 >= linemap[i].ga_len) {
change.dc_end[i] = MAXCOL;
change.dc_end_lnum_off[i] = INT_MAX;
} else {
change.dc_end[i] = ((linemap_entry_T *)linemap[i].ga_data)[diff_lnum_end - 1].byte_start +
((linemap_entry_T *)linemap[i].ga_data)[diff_lnum_end - 1].num_bytes;
change.dc_end_lnum_off[i] = ((linemap_entry_T *)linemap[i].ga_data)[diff_lnum_end -
1].lineoff;
}
}
GA_APPEND(diffline_change_T, &dp->df_changes, change);
}
done:
diff_algorithm = save_diff_algorithm;
dp->has_changes = true;
diff_clear(curtab);
curtab->tp_first_diff = orig_diff;
memcpy(curtab->tp_diffbuf, orig_diffbuf, sizeof(orig_diffbuf));
ga_clear(&file1_str);
ga_clear(&file2_str);
// No need to clear dio.dio_orig/dio_new because they were referencing
// strings that are now cleared.
clear_diffout(&dio.dio_diff);
for (int i = 0; i < DB_COUNT; i++) {
ga_clear(&linemap[i]);
}
}
/// Find the difference within a changed line.
/// Returns true if the line was added, no other buffer has it.
bool diff_find_change(win_T *wp, linenr_T lnum, diffline_T *diffline)
FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
{
int idx = diff_buf_idx(wp->w_buffer, curtab);
if (idx == DB_COUNT) { // cannot happen
return false;
}
// search for a change that includes "lnum" in the list of diffblocks.
diff_T *dp;
FOR_ALL_DIFFBLOCKS_IN_TAB(curtab, dp) {
if (lnum < dp->df_lnum[idx] + dp->df_count[idx]) {
break;
}
}
if (dp == NULL || diff_check_sanity(curtab, dp) == FAIL) {
return false;
}
int off = lnum - dp->df_lnum[idx];
if (!(diff_flags & ALL_INLINE_DIFF)) {
// Use simple algorithm
int change_start = MAXCOL; // first col of changed area
int change_end = -1; // last col of changed area
int ret = diff_find_change_simple(wp, lnum, dp, idx, &change_start, &change_end);
// convert from inclusive end to exclusive end per diffline's contract
change_end += 1;
// Create a mock diffline struct. We always only have one so no need to
// allocate memory.
CLEAR_FIELD(simple_diffline_change);
diffline->changes = &simple_diffline_change;
diffline->num_changes = 1;
diffline->bufidx = idx;
diffline->lineoff = lnum - dp->df_lnum[idx];
simple_diffline_change.dc_start[idx] = change_start;
simple_diffline_change.dc_end[idx] = change_end;
simple_diffline_change.dc_start_lnum_off[idx] = off;
simple_diffline_change.dc_end_lnum_off[idx] = off;
return ret;
}
// Use inline diff algorithm.
// The diff changes are usually cached so we check that first.
if (!dp->has_changes) {
diff_find_change_inline_diff(dp);
}
garray_T *changes = &dp->df_changes;
// Use linear search to find the first change for this line. We could
// optimize this to use binary search, but there should usually be a
// limited number of inline changes per diff block, and limited number of
// diff blocks shown on screen, so it is not necessary.
int num_changes = 0;
int change_idx = 0;
diffline->changes = NULL;
for (change_idx = 0; change_idx < changes->ga_len; change_idx++) {
diffline_change_T *change =
&((diffline_change_T *)dp->df_changes.ga_data)[change_idx];
if (change->dc_end_lnum_off[idx] < off) {
continue;
}
if (change->dc_start_lnum_off[idx] > off) {
break;
}
if (diffline->changes == NULL) {
diffline->changes = change;
}
num_changes++;
}
diffline->num_changes = num_changes;
diffline->bufidx = idx;
diffline->lineoff = off;
// Detect simple cases of added lines in the end within a diff block. This
// has to be the last change of this diff block, and all other buffers are
// considering this to be an addition past their last line. Other scenarios
// will be considered a changed line instead.
bool added = false;
if (num_changes == 1 && change_idx == dp->df_changes.ga_len) {
added = true;
for (int i = 0; i < DB_COUNT; i++) {
if (idx == i) {
continue;
}
if (curtab->tp_diffbuf[i] == NULL) {
continue;
}
diffline_change_T *change =
&((diffline_change_T *)dp->df_changes.ga_data)[dp->df_changes.ga_len - 1];
if (change->dc_start_lnum_off[i] != INT_MAX) {
added = false;
break;
}
}
}
return added;
}
/// Check that line "lnum" is not close to a diff block, this line should
/// be in a fold.
///
/// @param wp window containing the buffer to check
/// @param lnum line number to check within the buffer
///
/// @return false if there are no diff blocks at all in this window.
bool diff_infold(win_T *wp, linenr_T lnum)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ARG(1)
{
// Return if 'diff' isn't set.
if (!wp->w_p_diff) {
return false;
}
int idx = -1;
bool other = false;
for (int i = 0; i < DB_COUNT; i++) {
if (curtab->tp_diffbuf[i] == wp->w_buffer) {
idx = i;
} else if (curtab->tp_diffbuf[i] != NULL) {
other = true;
}
}
// return here if there are no diffs in the window
if ((idx == -1) || !other) {
return false;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
// Return if there are no diff blocks. All lines will be folded.
if (curtab->tp_first_diff == NULL) {
return true;
}
for (diff_T *dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
// If this change is below the line there can't be any further match.
if (dp->df_lnum[idx] - diff_context > lnum) {
break;
}
// If this change ends before the line we have a match.
if (dp->df_lnum[idx] + dp->df_count[idx] + diff_context > lnum) {
return false;
}
}
return true;
}
/// "dp" and "do" commands.
void nv_diffgetput(bool put, size_t count)
{
if (bt_prompt(curbuf)) {
vim_beep(kOptBoFlagOperator);
return;
}
exarg_T ea;
char buf[30];
if (count == 0) {
ea.arg = "";
} else {
vim_snprintf(buf, sizeof(buf), "%zu", count);
ea.arg = buf;
}
if (put) {
ea.cmdidx = CMD_diffput;
} else {
ea.cmdidx = CMD_diffget;
}
ea.addr_count = 0;
ea.line1 = curwin->w_cursor.lnum;
ea.line2 = curwin->w_cursor.lnum;
ex_diffgetput(&ea);
}
/// Return true if "diff" appears in the list of diff blocks of the current tab.
static bool valid_diff(diff_T *diff)
{
for (diff_T *dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
if (dp == diff) {
return true;
}
}
return false;
}
/// ":diffget" and ":diffput"
///
/// @param eap
void ex_diffgetput(exarg_T *eap)
{
int idx_other;
// Find the current buffer in the list of diff buffers.
int idx_cur = diff_buf_idx(curbuf, curtab);
if (idx_cur == DB_COUNT) {
emsg(_("E99: Current buffer is not in diff mode"));
return;
}
if (*eap->arg == NUL) {
bool found_not_ma = false;
// No argument: Find the other buffer in the list of diff buffers.
for (idx_other = 0; idx_other < DB_COUNT; idx_other++) {
if ((curtab->tp_diffbuf[idx_other] != curbuf)
&& (curtab->tp_diffbuf[idx_other] != NULL)) {
if ((eap->cmdidx != CMD_diffput)
|| MODIFIABLE(curtab->tp_diffbuf[idx_other])) {
break;
}
found_not_ma = true;
}
}
if (idx_other == DB_COUNT) {
if (found_not_ma) {
emsg(_("E793: No other buffer in diff mode is modifiable"));
} else {
emsg(_("E100: No other buffer in diff mode"));
}
return;
}
// Check that there isn't a third buffer in the list
for (int i = idx_other + 1; i < DB_COUNT; i++) {
if ((curtab->tp_diffbuf[i] != curbuf)
&& (curtab->tp_diffbuf[i] != NULL)
&& ((eap->cmdidx != CMD_diffput)
|| MODIFIABLE(curtab->tp_diffbuf[i]))) {
emsg(_("E101: More than two buffers in diff mode, don't know "
"which one to use"));
return;
}
}
} else {
// Buffer number or pattern given. Ignore trailing white space.
char *p = eap->arg + strlen(eap->arg);
while (p > eap->arg && ascii_iswhite(p[-1])) {
p--;
}
int i;
for (i = 0; ascii_isdigit(eap->arg[i]) && eap->arg + i < p; i++) {}
if (eap->arg + i == p) {
// digits only
i = (int)atol(eap->arg);
} else {
i = buflist_findpat(eap->arg, p, false, true, false);
if (i < 0) {
// error message already given
return;
}
}
buf_T *buf = buflist_findnr(i);
if (buf == NULL) {
semsg(_("E102: Can't find buffer \"%s\""), eap->arg);
return;
}
if (buf == curbuf) {
// nothing to do
return;
}
idx_other = diff_buf_idx(buf, curtab);
if (idx_other == DB_COUNT) {
semsg(_("E103: Buffer \"%s\" is not in diff mode"), eap->arg);
return;
}
}
diff_busy = true;
// When no range given include the line above or below the cursor.
if (eap->addr_count == 0) {
// Make it possible that ":diffget" on the last line gets line below
// the cursor line when there is no difference above the cursor.
int linestatus = 0;
if (eap->line1 == curbuf->b_ml.ml_line_count
&& (diff_check_with_linestatus(curwin, eap->line1, &linestatus) == 0
&& linestatus == 0)
&& (eap->line1 == 1
|| (diff_check_with_linestatus(curwin, eap->line1 - 1, &linestatus) >= 0
&& linestatus == 0))) {
eap->line2++;
} else if (eap->line1 > 0) {
eap->line1--;
}
}
aco_save_T aco;
if (eap->cmdidx != CMD_diffget) {
// Need to make the other buffer the current buffer to be able to make
// changes in it.
// Set curwin/curbuf to buf and save a few things.
aucmd_prepbuf(&aco, curtab->tp_diffbuf[idx_other]);
}
const int idx_from = eap->cmdidx == CMD_diffget ? idx_other : idx_cur;
const int idx_to = eap->cmdidx == CMD_diffget ? idx_cur : idx_other;
// May give the warning for a changed buffer here, which can trigger the
// FileChangedRO autocommand, which may do nasty things and mess
// everything up.
if (!curbuf->b_changed) {
change_warning(curbuf, 0);
if (diff_buf_idx(curbuf, curtab) != idx_to) {
emsg(_("E787: Buffer changed unexpectedly"));
goto theend;
}
}
diffgetput(eap->addr_count, idx_cur, idx_from, idx_to, eap->line1, eap->line2);
// restore curwin/curbuf and a few other things
if (eap->cmdidx != CMD_diffget) {
// Syncing undo only works for the current buffer, but we change
// another buffer. Sync undo if the command was typed. This isn't
// 100% right when ":diffput" is used in a function or mapping.
if (KeyTyped) {
u_sync(false);
}
aucmd_restbuf(&aco);
}
theend:
diff_busy = false;
if (diff_need_update) {
ex_diffupdate(NULL);
}
// Check that the cursor is on a valid character and update its
// position. When there were filler lines the topline has become
// invalid.
check_cursor(curwin);
changed_line_abv_curs();
// If all diffs are gone, update folds in all diff windows.
if (curtab->tp_first_diff == NULL) {
FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
if (wp->w_p_diff && wp->w_p_fdm[0] == 'd' && wp->w_p_fen) {
foldUpdateAll(wp);
}
}
}
if (diff_need_update) {
// redraw already done by ex_diffupdate()
diff_need_update = false;
} else {
// Also need to redraw the other buffers.
diff_redraw(false);
apply_autocmds(EVENT_DIFFUPDATED, NULL, NULL, false, curbuf);
}
}
/// Apply diffget/diffput to buffers and diffblocks
///
/// @param idx_cur index of "curbuf" before aucmd_prepbuf() in the list of diff buffers
/// @param idx_from index of the buffer to read from in the list of diff buffers
/// @param idx_to index of the buffer to modify in the list of diff buffers
static void diffgetput(const int addr_count, const int idx_cur, const int idx_from,
const int idx_to, const linenr_T line1, const linenr_T line2)
{
linenr_T off = 0;
diff_T *dprev = NULL;
for (diff_T *dp = curtab->tp_first_diff; dp != NULL;) {
if (!addr_count) {
// Handle the case with adjacent diff blocks (e.g. using linematch
// or anchors) at/above the cursor. Since a range wasn't specified,
// we just want to grab one diff block rather than all of them in
// the vicinity.
while (dp->df_next
&& dp->df_next->df_lnum[idx_cur] == dp->df_lnum[idx_cur] + dp->df_count[idx_cur]
&& dp->df_next->df_lnum[idx_cur] == line1 + off + 1) {
dprev = dp;
dp = dp->df_next;
}
}
if (dp->df_lnum[idx_cur] > line2 + off) {
// past the range that was specified
break;
}
diff_T dfree = { 0 };
bool did_free = false;
linenr_T lnum = dp->df_lnum[idx_to];
linenr_T count = dp->df_count[idx_to];
if ((dp->df_lnum[idx_cur] + dp->df_count[idx_cur] > line1 + off)
&& (u_save(lnum - 1, lnum + count) != FAIL)) {
// Inside the specified range and saving for undo worked.
linenr_T start_skip = 0;
linenr_T end_skip = 0;
if (addr_count > 0) {
// A range was specified: check if lines need to be skipped.
start_skip = line1 + off - dp->df_lnum[idx_cur];
if (start_skip > 0) {
// range starts below start of current diff block
if (start_skip > count) {
lnum += count;
count = 0;
} else {
count -= start_skip;
lnum += start_skip;
}
} else {
start_skip = 0;
}
end_skip = dp->df_lnum[idx_cur] + dp->df_count[idx_cur] - 1
- (line2 + off);
if (end_skip > 0) {
// range ends above end of current/from diff block
if (idx_cur == idx_from) {
// :diffput
count = MIN(count, dp->df_count[idx_cur] - start_skip - end_skip);
} else {
// :diffget
count -= end_skip;
end_skip = MAX(dp->df_count[idx_from] - start_skip - count, 0);
}
} else {
end_skip = 0;
}
}
bool buf_empty = buf_is_empty(curbuf);
int added = 0;
for (int i = 0; i < count; i++) {
// remember deleting the last line of the buffer
buf_empty = curbuf->b_ml.ml_line_count == 1;
if (ml_delete(lnum) == OK) {
added--;
}
}
for (int i = 0; i < dp->df_count[idx_from] - start_skip - end_skip; i++) {
linenr_T nr = dp->df_lnum[idx_from] + start_skip + i;
if (nr > curtab->tp_diffbuf[idx_from]->b_ml.ml_line_count) {
break;
}
char *p = xstrdup(ml_get_buf(curtab->tp_diffbuf[idx_from], nr));
ml_append(lnum + i - 1, p, 0, false);
xfree(p);
added++;
if (buf_empty && (curbuf->b_ml.ml_line_count == 2)) {
// Added the first line into an empty buffer, need to
// delete the dummy empty line.
// This has a side effect of incrementing curbuf->deleted_bytes,
// which results in inaccurate reporting of the byte count of
// previous contents in buffer-update events.
buf_empty = false;
ml_delete(2);
}
}
linenr_T new_count = dp->df_count[idx_to] + added;
dp->df_count[idx_to] = new_count;
if ((start_skip == 0) && (end_skip == 0)) {
// Check if there are any other buffers and if the diff is
// equal in them.
int i;
for (i = 0; i < DB_COUNT; i++) {
if ((curtab->tp_diffbuf[i] != NULL)
&& (i != idx_from)
&& (i != idx_to)
&& !diff_equal_entry(dp, idx_from, i)) {
break;
}
}
if (i == DB_COUNT) {
// delete the diff entry, the buffers are now equal here
dfree = *dp;
did_free = true;
dp = diff_free(curtab, dprev, dp);
}
}
if (added != 0) {
// Adjust marks. This will change the following entries!
mark_adjust(lnum, lnum + count - 1, MAXLNUM, added, kExtmarkNOOP);
if (curwin->w_cursor.lnum >= lnum) {
// Adjust the cursor position if it's in/after the changed
// lines.
if (curwin->w_cursor.lnum >= lnum + count) {
curwin->w_cursor.lnum += added;
} else if (added < 0) {
curwin->w_cursor.lnum = lnum;
}
}
}
extmark_adjust(curbuf, lnum, lnum + count - 1, MAXLNUM, added, kExtmarkUndo);
changed_lines(curbuf, lnum, 0, lnum + count, added, true);
if (did_free) {
// Diff is deleted, update folds in other windows.
diff_fold_update(&dfree, idx_to);
}
// mark_adjust() may have made "dp" invalid. We don't know where
// to continue then, bail out.
if (added != 0 && !valid_diff(dp)) {
break;
}
if (!did_free) {
// mark_adjust() may have changed the count in a wrong way
dp->df_count[idx_to] = new_count;
}
// When changing the current buffer, keep track of line numbers
if (idx_cur == idx_to) {
off += added;
}
}
// If before the range or not deleted, go to next diff.
if (!did_free) {
dprev = dp;
dp = dp->df_next;
}
}
}
/// Update folds for all diff buffers for entry "dp".
///
/// Skip buffer with index "skip_idx".
/// When there are no diffs, all folds are removed.
///
/// @param dp
/// @param skip_idx
static void diff_fold_update(diff_T *dp, int skip_idx)
{
FOR_ALL_WINDOWS_IN_TAB(wp, curtab) {
for (int i = 0; i < DB_COUNT; i++) {
if ((curtab->tp_diffbuf[i] == wp->w_buffer) && (i != skip_idx)) {
foldUpdate(wp, dp->df_lnum[i], dp->df_lnum[i] + dp->df_count[i]);
}
}
}
}
/// Checks that the buffer is in diff-mode.
///
/// @param buf buffer to check.
bool diff_mode_buf(buf_T *buf)
FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ARG(1)
{
FOR_ALL_TABS(tp) {
if (diff_buf_idx(buf, tp) != DB_COUNT) {
return true;
}
}
return false;
}
/// Move "count" times in direction "dir" to the next diff block.
///
/// @param dir
/// @param count
///
/// @return FAIL if there isn't such a diff block.
int diff_move_to(int dir, int count)
{
linenr_T lnum = curwin->w_cursor.lnum;
int idx = diff_buf_idx(curbuf, curtab);
if ((idx == DB_COUNT) || (curtab->tp_first_diff == NULL)) {
return FAIL;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
if (curtab->tp_first_diff == NULL) {
// no diffs today
return FAIL;
}
while (--count >= 0) {
// Check if already before first diff.
if ((dir == BACKWARD) && (lnum <= curtab->tp_first_diff->df_lnum[idx])) {
break;
}
diff_T *dp;
for (dp = curtab->tp_first_diff;; dp = dp->df_next) {
if (dp == NULL) {
break;
}
if (((dir == FORWARD) && (lnum < dp->df_lnum[idx]))
|| ((dir == BACKWARD)
&& ((dp->df_next == NULL)
|| (lnum <= dp->df_next->df_lnum[idx])))) {
lnum = dp->df_lnum[idx];
break;
}
}
}
// don't end up past the end of the file
lnum = MIN(lnum, curbuf->b_ml.ml_line_count);
// When the cursor didn't move at all we fail.
if (lnum == curwin->w_cursor.lnum) {
return FAIL;
}
setpcmark();
curwin->w_cursor.lnum = lnum;
curwin->w_cursor.col = 0;
return OK;
}
/// Return the line number in the current window that is closest to "lnum1" in
/// "buf1" in diff mode.
static linenr_T diff_get_corresponding_line_int(buf_T *buf1, linenr_T lnum1)
{
linenr_T baseline = 0;
int idx1 = diff_buf_idx(buf1, curtab);
int idx2 = diff_buf_idx(curbuf, curtab);
if ((idx1 == DB_COUNT)
|| (idx2 == DB_COUNT)
|| (curtab->tp_first_diff == NULL)) {
return lnum1;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
if (curtab->tp_first_diff == NULL) {
// no diffs today
return lnum1;
}
for (diff_T *dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
if (dp->df_lnum[idx1] > lnum1) {
return lnum1 - baseline;
}
if ((dp->df_lnum[idx1] + dp->df_count[idx1]) > lnum1) {
// Inside the diffblock
baseline = lnum1 - dp->df_lnum[idx1];
baseline = MIN(baseline, dp->df_count[idx2]);
return dp->df_lnum[idx2] + baseline;
}
if ((dp->df_lnum[idx1] == lnum1)
&& (dp->df_count[idx1] == 0)
&& (dp->df_lnum[idx2] <= curwin->w_cursor.lnum)
&& ((dp->df_lnum[idx2] + dp->df_count[idx2])
> curwin->w_cursor.lnum)) {
// Special case: if the cursor is just after a zero-count
// block (i.e. all filler) and the target cursor is already
// inside the corresponding block, leave the target cursor
// unmoved. This makes repeated CTRL-W W operations work
// as expected.
return curwin->w_cursor.lnum;
}
baseline = (dp->df_lnum[idx1] + dp->df_count[idx1])
- (dp->df_lnum[idx2] + dp->df_count[idx2]);
}
// If we get here then the cursor is after the last diff
return lnum1 - baseline;
}
/// Finds the corresponding line in a diff.
///
/// @param buf1
/// @param lnum1
///
/// @return The corresponding line.
linenr_T diff_get_corresponding_line(buf_T *buf1, linenr_T lnum1)
{
linenr_T lnum = diff_get_corresponding_line_int(buf1, lnum1);
// don't end up past the end of the file
return MIN(lnum, curbuf->b_ml.ml_line_count);
}
/// For line "lnum" in the current window find the equivalent lnum in window
/// "wp", compensating for inserted/deleted lines.
linenr_T diff_lnum_win(linenr_T lnum, win_T *wp)
{
diff_T *dp;
int idx = diff_buf_idx(curbuf, curtab);
if (idx == DB_COUNT) {
// safety check
return 0;
}
if (curtab->tp_diff_invalid) {
// update after a big change
ex_diffupdate(NULL);
}
// search for a change that includes "lnum" in the list of diffblocks.
for (dp = curtab->tp_first_diff; dp != NULL; dp = dp->df_next) {
if (lnum <= dp->df_lnum[idx] + dp->df_count[idx]) {
break;
}
}
// When after the last change, compute relative to the last line number.
if (dp == NULL) {
return wp->w_buffer->b_ml.ml_line_count
- (curbuf->b_ml.ml_line_count - lnum);
}
// Find index for "wp".
int i = diff_buf_idx(wp->w_buffer, curtab);
if (i == DB_COUNT) {
// safety check
return 0;
}
linenr_T n = lnum + (dp->df_lnum[i] - dp->df_lnum[idx]);
return MIN(n, dp->df_lnum[i] + dp->df_count[i]);
}
/// Handle an ED style diff line.
///
/// @return FAIL if the line does not contain diff info.
static int parse_diff_ed(char *line, diffhunk_T *hunk)
{
int l1, l2;
// The line must be one of three formats:
// change: {first}[,{last}]c{first}[,{last}]
// append: {first}a{first}[,{last}]
// delete: {first}[,{last}]d{first}
char *p = line;
linenr_T f1 = getdigits_int32(&p, true, 0);
if (*p == ',') {
p++;
l1 = getdigits_int(&p, true, 0);
} else {
l1 = f1;
}
if (*p != 'a' && *p != 'c' && *p != 'd') {
return FAIL; // invalid diff format
}
int difftype = (uint8_t)(*p++);
int f2 = getdigits_int(&p, true, 0);
if (*p == ',') {
p++;
l2 = getdigits_int(&p, true, 0);
} else {
l2 = f2;
}
if (l1 < f1 || l2 < f2) {
return FAIL;
}
if (difftype == 'a') {
hunk->lnum_orig = f1 + 1;
hunk->count_orig = 0;
} else {
hunk->lnum_orig = f1;
hunk->count_orig = l1 - f1 + 1;
}
if (difftype == 'd') {
hunk->lnum_new = (linenr_T)f2 + 1;
hunk->count_new = 0;
} else {
hunk->lnum_new = (linenr_T)f2;
hunk->count_new = l2 - f2 + 1;
}
return OK;
}
/// Parses unified diff with zero(!) context lines.
/// Return FAIL if there is no diff information in "line".
static int parse_diff_unified(char *line, diffhunk_T *hunk)
{
// Parse unified diff hunk header:
// @@ -oldline,oldcount +newline,newcount @@
char *p = line;
if (*p++ == '@' && *p++ == '@' && *p++ == ' ' && *p++ == '-') {
int oldcount;
linenr_T newline;
int newcount;
linenr_T oldline = getdigits_int32(&p, true, 0);
if (*p == ',') {
p++;
oldcount = getdigits_int(&p, true, 0);
} else {
oldcount = 1;
}
if (*p++ == ' ' && *p++ == '+') {
newline = getdigits_int(&p, true, 0);
if (*p == ',') {
p++;
newcount = getdigits_int(&p, true, 0);
} else {
newcount = 1;
}
} else {
return FAIL; // invalid diff format
}
if (oldcount == 0) {
oldline += 1;
}
if (newcount == 0) {
newline += 1;
}
if (newline == 0) {
newline = 1;
}
hunk->lnum_orig = oldline;
hunk->count_orig = oldcount;
hunk->lnum_new = newline;
hunk->count_new = newcount;
return OK;
}
return FAIL;
}
/// Callback function for the xdl_diff() function.
/// Stores the diff output in a grow array.
static int xdiff_out(int start_a, int count_a, int start_b, int count_b, void *priv)
{
diffout_T *dout = (diffout_T *)priv;
GA_APPEND(diffhunk_T, &(dout->dout_ga), ((diffhunk_T){
.lnum_orig = (linenr_T)start_a + 1,
.count_orig = count_a,
.lnum_new = (linenr_T)start_b + 1,
.count_new = count_b,
}));
return 0;
}
/// "diff_filler()" function
void f_diff_filler(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
{
rettv->vval.v_number = MAX(0, diff_check_fill(curwin, tv_get_lnum(argvars)));
}
/// "diff_hlID()" function
void f_diff_hlID(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
{
static linenr_T prev_lnum = 0;
static varnumber_T changedtick = 0;
static int fnum = 0;
static int prev_diff_flags = 0;
static int change_start = 0;
static int change_end = 0;
static hlf_T hlID = (hlf_T)0;
diffline_T diffline = { 0 };
// Remember the results if using simple since it's recalculated per
// call. Otherwise just call diff_find_change() every time since
// internally the result is cached internally.
const bool cache_results = !(diff_flags & ALL_INLINE_DIFF);
linenr_T lnum = tv_get_lnum(argvars);
if (lnum < 0) { // ignore type error in {lnum} arg
lnum = 0;
}
if (!cache_results
|| lnum != prev_lnum
|| changedtick != buf_get_changedtick(curbuf)
|| fnum != curbuf->b_fnum
|| diff_flags != prev_diff_flags) {
// New line, buffer, change: need to get the values.
int linestatus = 0;
diff_check_with_linestatus(curwin, lnum, &linestatus);
if (linestatus < 0) {
if (linestatus == -1) {
change_start = MAXCOL;
change_end = -1;
if (diff_find_change(curwin, lnum, &diffline)) {
hlID = HLF_ADD; // added line
} else {
hlID = HLF_CHD; // changed line
if (diffline.num_changes > 0 && cache_results) {
change_start = diffline.changes[0].dc_start[diffline.bufidx];
change_end = diffline.changes[0].dc_end[diffline.bufidx];
}
}
} else {
hlID = HLF_ADD; // added line
}
} else {
hlID = (hlf_T)0;
}
if (cache_results) {
prev_lnum = lnum;
changedtick = buf_get_changedtick(curbuf);
fnum = curbuf->b_fnum;
prev_diff_flags = diff_flags;
}
}
if (hlID == HLF_CHD || hlID == HLF_TXD) {
int col = (int)tv_get_number(&argvars[1]) - 1; // Ignore type error in {col}.
if (cache_results) {
if (col >= change_start && col < change_end) {
hlID = HLF_TXD; // Changed text.
} else {
hlID = HLF_CHD; // Changed line.
}
} else {
hlID = HLF_CHD;
for (int i = 0; i < diffline.num_changes; i++) {
bool added = diff_change_parse(&diffline, &diffline.changes[i],
&change_start, &change_end);
if (col >= change_start && col < change_end) {
hlID = added ? HLF_TXA : HLF_TXD;
break;
}
if (col < change_start) {
// the remaining changes are past this column and not relevant
break;
}
}
}
}
rettv->vval.v_number = hlID;
}