Added portable file and directory operations (thanks @icculus!)

src/filesystem/posix/SDL_sysfsops.c

@@ -0,0 +1,138 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_internal.h"
+
+#if defined(SDL_FSOPS_POSIX)
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <dirent.h>
+#include <sys/stat.h>
+
+#include "../SDL_sysfilesystem.h"
+
+int SDL_SYS_FSenumerate(const char *fullpath, const char *dirname, SDL_EnumerateDirectoryCallback cb, void *userdata)
+{
+    int retval = 1;
+
+    DIR *dir = opendir(fullpath);
+    if (!dir) {
+        return SDL_SetError("Can't open directory: %s", strerror(errno));
+    }
+
+    struct dirent *ent;
+    while ((retval == 1) && ((ent = readdir(dir)) != NULL))
+    {
+        const char *name = ent->d_name;
+        if ((SDL_strcmp(name, ".") == 0) || (SDL_strcmp(name, "..") == 0)) {
+            continue;
+        }
+        retval = cb(userdata, NULL, dirname, name);
+    }
+
+    closedir(dir);
+
+    return retval;
+}
+
+int SDL_SYS_FSremove(const char *fullpath)
+{
+    int rc = remove(fullpath);
+    if (rc < 0) {
+        const int origerrno = errno;
+        if (origerrno == ENOENT) {
+            char *parent = SDL_strdup(fullpath);
+            if (!parent) {
+                return -1;
+            }
+
+            char *ptr = SDL_strrchr(parent, '/');
+            if (ptr) {
+                *ptr = '\0';  // chop off thing we were removing, see if parent is there.
+            }
+
+            struct stat statbuf;
+            rc = stat(ptr ? parent : ".", &statbuf);
+            SDL_free(parent);
+            if (rc == 0) {
+                return 0;  // it's already gone, and parent exists, consider it success.
+            }
+        }
+        return SDL_SetError("Can't remove path: %s", strerror(origerrno));
+    }
+    return 0;
+}
+
+int SDL_SYS_FSrename(const char *oldfullpath, const char *newfullpath)
+{
+    if (rename(oldfullpath, newfullpath) < 0) {
+        return SDL_SetError("Can't remove path: %s", strerror(errno));
+    }
+    return 0;
+}
+
+int SDL_SYS_FSmkdir(const char *fullpath)
+{
+    const int rc = mkdir(fullpath, 0770);
+    if (rc < 0) {
+        const int origerrno = errno;
+        if (origerrno == EEXIST) {
+            struct stat statbuf;
+            if ((stat(fullpath, &statbuf) == 0) && (S_ISDIR(statbuf.st_mode))) {
+                return 0;  // it already exists and it's a directory, consider it success.
+            }
+        }
+        return SDL_SetError("Can't create directory: %s", strerror(origerrno));
+    }
+    return 0;
+}
+
+int SDL_SYS_FSstat(const char *fullpath, SDL_PathInfo *info)
+{
+    struct stat statbuf;
+    const int rc = stat(fullpath, &statbuf);
+    if (rc < 0) {
+        return SDL_SetError("Can't stat: %s", strerror(errno));
+    } else if (S_ISREG(statbuf.st_mode)) {
+        info->type = SDL_PATHTYPE_FILE;
+        info->size = (Uint64) statbuf.st_size;
+    } else if (S_ISDIR(statbuf.st_mode)) {
+        info->type = SDL_PATHTYPE_DIRECTORY;
+        info->size = 0;
+    } else {
+        info->type = SDL_PATHTYPE_OTHER;
+        info->size = (Uint64) statbuf.st_size;
+    }
+
+    // SDL file time is seconds since the Unix epoch, so we're already good here.
+    // Note that this will fail on machines with 32-bit time_t in 2038, but that's not
+    // an SDL bug; those machines need to be fixed or everything will fail in the same way.
+    info->create_time = (Sint64) statbuf.st_ctime;
+    info->modify_time = (Sint64) statbuf.st_mtime;
+    info->access_time = (Sint64) statbuf.st_atime;
+
+    return 0;
+}
+
+#endif
+