Added SDL_CopyFile() and SDL_CopyStorageFile()

Fixes https://github.com/libsdl-org/SDL/issues/9553

include/SDL3/SDL_filesystem.h

@@ -327,6 +327,18 @@ extern SDL_DECLSPEC int SDLCALL SDL_RemovePath(const char *path);
  */
 extern SDL_DECLSPEC int SDLCALL SDL_RenamePath(const char *oldpath, const char *newpath);
 
+/**
+ * Copy a file.
+ *
+ * \param oldpath the old path.
+ * \param newpath the new path.
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 3.0.0.
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_CopyFile(const char *oldpath, const char *newpath);
+
 /**
  * Get information about a filesystem path.
  *

include/SDL3/SDL_storage.h

@@ -83,6 +83,9 @@ typedef struct SDL_StorageInterface
     /* Rename a path, optional for read-only storage */
     int (SDLCALL *rename)(void *userdata, const char *oldpath, const char *newpath);
 
+    /* Copy a file, optional for read-only storage */
+    int (SDLCALL *copy)(void *userdata, const char *oldpath, const char *newpath);
+
     /* Get the space remaining, optional for read-only storage */
     Uint64 (SDLCALL *space_remaining)(void *userdata);
 } SDL_StorageInterface;
@@ -337,6 +340,21 @@ extern SDL_DECLSPEC int SDLCALL SDL_RemoveStoragePath(SDL_Storage *storage, cons
  */
 extern SDL_DECLSPEC int SDLCALL SDL_RenameStoragePath(SDL_Storage *storage, const char *oldpath, const char *newpath);
 
+/**
+ * Copy a file in a writable storage container.
+ *
+ * \param storage a storage container.
+ * \param oldpath the old path.
+ * \param newpath the new path.
+ * \returns 0 on success or a negative error code on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_StorageReady
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_CopyStorageFile(SDL_Storage *storage, const char *oldpath, const char *newpath);
+
 /**
  * Get information about a filesystem path in a storage container.
  *

src/dynapi/SDL_dynapi.sym

@@ -55,7 +55,9 @@ SDL3_0.0.0 {
     SDL_ConvertPixelsAndColorspace;
     SDL_ConvertSurface;
     SDL_ConvertSurfaceAndColorspace;
+    SDL_CopyFile;
     SDL_CopyProperties;
+    SDL_CopyStorageFile;
     SDL_CreateAudioStream;
     SDL_CreateColorCursor;
     SDL_CreateCondition;

src/dynapi/SDL_dynapi_overrides.h

@@ -80,7 +80,9 @@
 #define SDL_ConvertPixelsAndColorspace SDL_ConvertPixelsAndColorspace_REAL
 #define SDL_ConvertSurface SDL_ConvertSurface_REAL
 #define SDL_ConvertSurfaceAndColorspace SDL_ConvertSurfaceAndColorspace_REAL
+#define SDL_CopyFile SDL_CopyFile_REAL
 #define SDL_CopyProperties SDL_CopyProperties_REAL
+#define SDL_CopyStorageFile SDL_CopyStorageFile_REAL
 #define SDL_CreateAudioStream SDL_CreateAudioStream_REAL
 #define SDL_CreateColorCursor SDL_CreateColorCursor_REAL
 #define SDL_CreateCondition SDL_CreateCondition_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -100,7 +100,9 @@ SDL_DYNAPI_PROC(int,SDL_ConvertPixels,(int a, int b, SDL_PixelFormat c, const vo
 SDL_DYNAPI_PROC(int,SDL_ConvertPixelsAndColorspace,(int a, int b, SDL_PixelFormat c, SDL_Colorspace d, SDL_PropertiesID e, const void *f, int g, SDL_PixelFormat h, SDL_Colorspace i, SDL_PropertiesID j, void *k, int l),(a,b,c,d,e,f,g,h,i,j,k,l),return)
 SDL_DYNAPI_PROC(SDL_Surface*,SDL_ConvertSurface,(SDL_Surface *a, SDL_PixelFormat b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_Surface*,SDL_ConvertSurfaceAndColorspace,(SDL_Surface *a, SDL_PixelFormat b, SDL_Palette *c, SDL_Colorspace d, SDL_PropertiesID e),(a,b,c,d,e),return)
+SDL_DYNAPI_PROC(int,SDL_CopyFile,(const char *a, const char *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_CopyProperties,(SDL_PropertiesID a, SDL_PropertiesID b),(a,b),return)
+SDL_DYNAPI_PROC(int,SDL_CopyStorageFile,(SDL_Storage *a, const char *b, const char *c),(a,b,c),return)
 SDL_DYNAPI_PROC(SDL_AudioStream*,SDL_CreateAudioStream,(const SDL_AudioSpec *a, const SDL_AudioSpec *b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_Cursor*,SDL_CreateColorCursor,(SDL_Surface *a, int b, int c),(a,b,c),return)
 SDL_DYNAPI_PROC(SDL_Condition*,SDL_CreateCondition,(void),(),return)

src/filesystem/SDL_filesystem.c

@@ -43,6 +43,16 @@ int SDL_RenamePath(const char *oldpath, const char *newpath)
     return SDL_SYS_RenamePath(oldpath, newpath);
 }
 
+int SDL_CopyFile(const char *oldpath, const char *newpath)
+{
+    if (!oldpath) {
+        return SDL_InvalidParamError("oldpath");
+    } else if (!newpath) {
+        return SDL_InvalidParamError("newpath");
+    }
+    return SDL_SYS_CopyFile(oldpath, newpath);
+}
+
 int SDL_CreateDirectory(const char *path)
 {
     /* TODO: Recursively create subdirectories */

src/filesystem/SDL_sysfilesystem.h

@@ -30,6 +30,7 @@ extern char *SDL_SYS_GetUserFolder(SDL_Folder folder);
 int SDL_SYS_EnumerateDirectory(const char *path, const char *dirname, SDL_EnumerateDirectoryCallback cb, void *userdata);
 int SDL_SYS_RemovePath(const char *path);
 int SDL_SYS_RenamePath(const char *oldpath, const char *newpath);
+int SDL_SYS_CopyFile(const char *oldpath, const char *newpath);
 int SDL_SYS_CreateDirectory(const char *path);
 int SDL_SYS_GetPathInfo(const char *path, SDL_PathInfo *info);
 

src/filesystem/dummy/SDL_sysfsops.c

@@ -43,6 +43,11 @@ int SDL_SYS_RenamePath(const char *oldpath, const char *newpath)
     return SDL_Unsupported();
 }
 
+int SDL_SYS_CopyFile(const char *oldpath, const char *newpath)
+{
+    return SDL_Unsupported();
+}
+
 int SDL_SYS_CreateDirectory(const char *path)
 {
     return SDL_Unsupported();

src/filesystem/posix/SDL_sysfsops.c

@@ -79,6 +79,73 @@ int SDL_SYS_RenamePath(const char *oldpath, const char *newpath)
     return 0;
 }
 
+int SDL_SYS_CopyFile(const char *oldpath, const char *newpath)
+{
+    char *buffer = NULL;
+    char *tmppath = NULL;
+    SDL_IOStream *input = NULL;
+    SDL_IOStream *output = NULL;
+    const size_t maxlen = 4096;
+    size_t len;
+    int retval = -1;
+
+    if (SDL_asprintf(&tmppath, "%s.tmp", newpath) < 0) {
+        goto done;
+    }
+
+    input = SDL_IOFromFile(oldpath, "rb");
+    if (!input) {
+        goto done;
+    }
+
+    output = SDL_IOFromFile(tmppath, "wb");
+    if (!output) {
+        goto done;
+    }
+
+    buffer = (char *)SDL_malloc(maxlen);
+    if (!buffer) {
+        goto done;
+    }
+
+    while ((len = SDL_ReadIO(input, buffer, maxlen)) > 0) {
+        if (SDL_WriteIO(output, buffer, len) < len) {
+            goto done;
+        }
+    }
+    if (SDL_GetIOStatus(input) != SDL_IO_STATUS_EOF) {
+        goto done;
+    }
+
+    SDL_CloseIO(input);
+    input = NULL;
+
+    if (SDL_CloseIO(output) < 0) {
+        goto done;
+    }
+    output = NULL;
+
+    if (SDL_RenamePath(tmppath, newpath) < 0) {
+        SDL_RemovePath(tmppath);
+        goto done;
+    }
+
+    retval = 0;
+
+done:
+    if (output) {
+        SDL_CloseIO(output);
+        SDL_RemovePath(tmppath);
+    }
+    if (input) {
+        SDL_CloseIO(input);
+    }
+    SDL_free(tmppath);
+    SDL_free(buffer);
+
+    return retval;
+}
+
 int SDL_SYS_CreateDirectory(const char *path)
 {
     const int rc = mkdir(path, 0770);

src/filesystem/windows/SDL_sysfsops.c

@@ -131,6 +131,25 @@ int SDL_SYS_RenamePath(const char *oldpath, const char *newpath)
     return !rc ? WIN_SetError("Couldn't rename path") : 0;
 }
 
+int SDL_SYS_CopyFile(const char *oldpath, const char *newpath)
+{
+    WCHAR *woldpath = WIN_UTF8ToStringW(oldpath);
+    if (!woldpath) {
+        return -1;
+    }
+
+    WCHAR *wnewpath = WIN_UTF8ToStringW(newpath);
+    if (!wnewpath) {
+        SDL_free(woldpath);
+        return -1;
+    }
+
+    const BOOL rc = CopyFileW(woldpath, wnewpath, TRUE);
+    SDL_free(wnewpath);
+    SDL_free(woldpath);
+    return !rc ? WIN_SetError("Couldn't copy path") : 0;
+}
+
 int SDL_SYS_CreateDirectory(const char *path)
 {
     WCHAR *wpath = WIN_UTF8ToStringW(path);

src/storage/SDL_storage.c

@@ -291,6 +291,24 @@ int SDL_RenameStoragePath(SDL_Storage *storage, const char *oldpath, const char
     return storage->iface.rename(storage->userdata, oldpath, newpath);
 }
 
+int SDL_CopyStorageFile(SDL_Storage *storage, const char *oldpath, const char *newpath)
+{
+    CHECK_STORAGE_MAGIC()
+
+    if (!oldpath) {
+        return SDL_InvalidParamError("oldpath");
+    }
+    if (!newpath) {
+        return SDL_InvalidParamError("newpath");
+    }
+
+    if (!storage->iface.copy) {
+        return SDL_Unsupported();
+    }
+
+    return storage->iface.copy(storage->userdata, oldpath, newpath);
+}
+
 int SDL_GetStoragePathInfo(SDL_Storage *storage, const char *path, SDL_PathInfo *info)
 {
     SDL_PathInfo dummy;

src/storage/generic/SDL_genericstorage.c

@@ -160,6 +160,21 @@ static int GENERIC_RenameStoragePath(void *userdata, const char *oldpath, const
     return result;
 }
 
+static int GENERIC_CopyStorageFile(void *userdata, const char *oldpath, const char *newpath)
+{
+    int result = -1;
+
+    char *fulloldpath = GENERIC_INTERNAL_CreateFullPath((char *)userdata, oldpath);
+    char *fullnewpath = GENERIC_INTERNAL_CreateFullPath((char *)userdata, newpath);
+    if (fulloldpath && fullnewpath) {
+        result = SDL_CopyFile(fulloldpath, fullnewpath);
+    }
+    SDL_free(fulloldpath);
+    SDL_free(fullnewpath);
+
+    return result;
+}
+
 static Uint64 GENERIC_GetStorageSpaceRemaining(void *userdata)
 {
     /* TODO: There's totally a way to query a folder root's quota... */
@@ -176,6 +191,7 @@ static const SDL_StorageInterface GENERIC_title_iface = {
     NULL,   /* mkdir */
     NULL,   /* remove */
     NULL,   /* rename */
+    NULL,   /* copy */
     NULL    /* space_remaining */
 };
 
@@ -219,6 +235,7 @@ static const SDL_StorageInterface GENERIC_user_iface = {
     GENERIC_CreateStorageDirectory,
     GENERIC_RemoveStoragePath,
     GENERIC_RenameStoragePath,
+    GENERIC_CopyStorageFile,
     GENERIC_GetStorageSpaceRemaining
 };
 
@@ -257,6 +274,7 @@ static const SDL_StorageInterface GENERIC_file_iface = {
     GENERIC_CreateStorageDirectory,
     GENERIC_RemoveStoragePath,
     GENERIC_RenameStoragePath,
+    GENERIC_CopyStorageFile,
     GENERIC_GetStorageSpaceRemaining
 };
 

src/storage/steam/SDL_steamstorage.c

@@ -140,6 +140,7 @@ static const SDL_StorageInterface STEAM_user_iface = {
     NULL,   /* mkdir */
     NULL,   /* remove */
     NULL,   /* rename */
+    NULL,   /* copy */
     STEAM_GetStorageSpaceRemaining
 };
 

test/testfilesystem.c

@@ -109,6 +109,8 @@ int main(int argc, char *argv[])
 
     if (base_path) {
         const char * const *globlist;
+        SDL_IOStream *stream;
+        const char *text = "foo\n";
 
         if (SDL_EnumerateDirectory(base_path, enum_callback, NULL) < 0) {
             SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Base path enumeration failed!");
@@ -140,6 +142,42 @@ int main(int argc, char *argv[])
         } else if (SDL_RemovePath("testfilesystem-test") == -1) {  /* THIS SHOULD NOT FAIL! Removing a directory that is already gone should succeed here. */
             SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_RemovePath('testfilesystem-test') failed: %s", SDL_GetError());
         }
+
+        stream = SDL_IOFromFile("testfilesystem-A", "wb");
+        if (stream) {
+            SDL_WriteIO(stream, text, SDL_strlen(text));
+            SDL_CloseIO(stream);
+
+            if (SDL_RenamePath("testfilesystem-A", "testfilesystem-B") < 0) {
+                SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_RenamePath('testfilesystem-A', 'testfilesystem-B') failed: %s", SDL_GetError());
+            } else if (SDL_CopyFile("testfilesystem-B", "testfilesystem-A") < 0) {
+                SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_CopyFile('testfilesystem-B', 'testfilesystem-A') failed: %s", SDL_GetError());
+            } else {
+                size_t sizeA, sizeB;
+                char *textA, *textB;
+
+                textA = (char *)SDL_LoadFile("testfilesystem-A", &sizeA);
+                if (!textA || sizeA != SDL_strlen(text) || SDL_strcmp(textA, text) != 0) {
+                    SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Contents of testfilesystem-A didn't match, expected %s, got %s\n", text, textA);
+                }
+                SDL_free(textA);
+
+                textB = (char *)SDL_LoadFile("testfilesystem-B", &sizeB);
+                if (!textB || sizeB != SDL_strlen(text) || SDL_strcmp(textB, text) != 0) {
+                    SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Contents of testfilesystem-B didn't match, expected %s, got %s\n", text, textB);
+                }
+                SDL_free(textB);
+            }
+
+            if (SDL_RemovePath("testfilesystem-A") < 0) {
+                SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_RemovePath('testfilesystem-A') failed: %s", SDL_GetError());
+            }
+            if (SDL_RemovePath("testfilesystem-B") < 0) {
+                SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_RemovePath('testfilesystem-B') failed: %s", SDL_GetError());
+            }
+        } else {
+            SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_IOFromFile('testfilesystem-A', 'w') failed: %s", SDL_GetError());
+        }
     }
 
     SDL_Quit();