summaryrefslogtreecommitdiff
path: root/libnsgif.c
diff options
context:
space:
mode:
Diffstat (limited to 'libnsgif.c')
-rw-r--r--libnsgif.c71
1 files changed, 36 insertions, 35 deletions
diff --git a/libnsgif.c b/libnsgif.c
index d243d62..6979ceb 100644
--- a/libnsgif.c
+++ b/libnsgif.c
@@ -67,8 +67,8 @@
/* Internal GIF routines
*/
-static int gif_initialise_sprite(struct gif_animation *gif, unsigned int width, unsigned int height, gif_bitmap_callback_vt *bitmap_callbacks);
-static int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks);
+static gif_result gif_initialise_sprite(struct gif_animation *gif, unsigned int width, unsigned int height, gif_bitmap_callback_vt *bitmap_callbacks);
+static gif_result gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks);
static unsigned int gif_interlaced_line(int height, int y);
@@ -102,7 +102,7 @@ static bool get_done;
*/
static bool clear_image = false;
-/* Initialises any workspace held by the animation and attempts to decode
+/** Initialises any workspace held by the animation and attempts to decode
any information that hasn't already been decoded.
If an error occurs, all previously decoded frames are retained.
@@ -112,10 +112,10 @@ static bool clear_image = false;
GIF_INSUFFICIENT_MEMORY for memory error
GIF_DATA_ERROR for GIF error
GIF_INSUFFICIENT_DATA for insufficient data to do anything
- 0 for successful decoding
- 1 for successful decoding (all frames completely read)
+ GIF_OK for successful decoding
+ GIF_WORKING for successful decoding if more frames are expected
*/
-int gif_initialise(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks) {
+gif_result gif_initialise(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks) {
unsigned char *gif_data;
unsigned int index;
int return_value;
@@ -225,7 +225,7 @@ int gif_initialise(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_cal
*/
if (gif->buffer_size == 14) {
if (gif_data[0] == GIF_TRAILER)
- return 1;
+ return GIF_OK;
else
return GIF_INSUFFICIENT_DATA;
}
@@ -274,9 +274,9 @@ int gif_initialise(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_cal
}
}
- /* Repeatedly try to decode frames
+ /* Repeatedly try to initialise frames
*/
- while ((return_value = gif_initialise_frame(gif, bitmap_callbacks)) == 0);
+ while ((return_value = gif_initialise_frame(gif, bitmap_callbacks)) == GIF_WORKING);
/* If there was a memory error tell the caller
*/
@@ -299,10 +299,10 @@ int gif_initialise(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_cal
/** Updates the sprite memory size
- @return -3 for a memory error
- 0 for success
+ @return GIF_INSUFFICIENT_MEMORY for a memory error
+ GIF_OK for success
*/
-static int gif_initialise_sprite(struct gif_animation *gif, unsigned int width, unsigned int height, gif_bitmap_callback_vt *bitmap_callbacks) {
+static gif_result gif_initialise_sprite(struct gif_animation *gif, unsigned int width, unsigned int height, gif_bitmap_callback_vt *bitmap_callbacks) {
unsigned int max_width;
unsigned int max_height;
struct bitmap *buffer;
@@ -310,7 +310,7 @@ static int gif_initialise_sprite(struct gif_animation *gif, unsigned int width,
/* Check if we've changed
*/
if ((width <= gif->width) && (height <= gif->height))
- return 0;
+ return GIF_OK;
/* Get our maximum values
*/
@@ -329,20 +329,21 @@ static int gif_initialise_sprite(struct gif_animation *gif, unsigned int width,
/* Invalidate our currently decoded image
*/
gif->decoded_frame = -1;
- return 0;
+ return GIF_OK;
}
-/* Attempts to initialise the next frame
+/** Attempts to initialise the next frame
- @return -4 for insufficient data to process the entire frame
- -3 for a memory error
- -2 for a data error
- -1 for insufficient data to process anything
- 0 for success
- 1 for success (GIF terminator found)
+ @return GIF_INSUFFICIENT_DATA for insufficient data to do anything
+ GIF_FRAME_DATA_ERROR for GIF frame data error
+ GIF_INSUFFICIENT_MEMORY for insufficient memory to process
+ GIF_INSUFFICIENT_FRAME_DATA for insufficient data to complete the frame
+ GIF_DATA_ERROR for GIF error (invalid frame header)
+ GIF_OK for successful decoding
+ GIF_WORKING for successful decoding if more frames are expected
*/
-int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks) {
+gif_result gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitmap_callbacks) {
int frame;
gif_frame *temp_buf;
@@ -368,17 +369,17 @@ int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitm
/* Check if we've finished
*/
- if ((gif_bytes > 0) && (gif_data[0] == GIF_TRAILER)) return 1;
+ if ((gif_bytes > 0) && (gif_data[0] == GIF_TRAILER)) return GIF_OK;
/* Check if we have enough data
* The shortest block of data is a 4-byte comment extension + 1-byte block terminator + 1-byte gif trailer
*/
- if (gif_bytes < 6) return GIF_INSUFFICIENT_FRAME_DATA;
+ if (gif_bytes < 6) return GIF_INSUFFICIENT_DATA;
/* We could theoretically get some junk data that gives us millions of frames, so
we ensure that we don't have a silly number
*/
- if (frame > 4096) return GIF_DATA_ERROR;
+ if (frame > 4096) return GIF_FRAME_DATA_ERROR;
/* Get some memory to store our pointers in etc.
*/
@@ -469,7 +470,7 @@ int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitm
else if (gif_data[0] == GIF_TRAILER) {
gif->buffer_position = gif_data - gif->gif_data;
gif->frame_count = frame + 1;
- return 1;
+ return GIF_OK;
}
/* If we're not done, there should be an image descriptor
@@ -571,8 +572,8 @@ int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitm
if (gif_bytes < 1)
return GIF_INSUFFICIENT_FRAME_DATA;
else
- if (gif_data[0] == GIF_TRAILER) return 1;
- return 0;
+ if (gif_data[0] == GIF_TRAILER) return GIF_OK;
+ return GIF_WORKING;
}
@@ -582,11 +583,11 @@ int gif_initialise_frame(struct gif_animation *gif, gif_bitmap_callback_vt *bitm
GIF_INSUFFICIENT_FRAME_DATA for insufficient data to complete the frame
GIF_DATA_ERROR for GIF error (invalid frame header)
GIF_INSUFFICIENT_DATA for insufficient data to do anything
- 0 for successful decoding
- If a frame does not contain any image data, 0 is returned and
+ GIF_OK for successful decoding
+ If a frame does not contain any image data, GIF_OK is returned and
gif->current_error is set to GIF_FRAME_NO_DISPLAY
*/
-int gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_callback_vt *bitmap_callbacks) {
+gif_result gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_callback_vt *bitmap_callbacks) {
unsigned int index = 0;
unsigned char *gif_data;
unsigned char *gif_end;
@@ -611,7 +612,7 @@ int gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_c
gif->current_error = 0;
if (gif->frames[frame].display == false) {
gif->current_error = GIF_FRAME_NO_DISPLAY;
- return 0;
+ return GIF_OK;
}
/* Ensure we have a frame to decode
@@ -619,7 +620,7 @@ int gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_c
if (frame > gif->frame_count_partial)
return GIF_INSUFFICIENT_DATA;
if ((!clear_image) && ((int)frame == gif->decoded_frame))
- return 0;
+ return GIF_OK;
/* If the previous frame was dirty, remove it
*/
@@ -794,7 +795,7 @@ int gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_c
return_value = GIF_INSUFFICIENT_FRAME_DATA;
break;
} else if (gif_data[0] == GIF_TRAILER) {
- return_value = 1;
+ return_value = GIF_OK;
break;
}
@@ -809,7 +810,7 @@ int gif_decode_frame(struct gif_animation *gif, unsigned int frame, gif_bitmap_c
/* If we only have the 1-byte LZW code size + 1-byte gif trailer, we're finished
*/
} else if ((gif_bytes = 2) && (gif_data[1] == GIF_TRAILER)) {
- return_value = 1;
+ return_value = GIF_OK;
break;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-25 04:01:02 +0000