commit ff5bbfae5214d8291c8eb93670233909ded5b722
Author: FRIGN <dev_AT_frign.de>
AuthorDate: Wed Jan 6 12:30:17 2016 +0100
Commit: FRIGN <dev_AT_frign.de>
CommitDate: Wed Jan 6 12:32:48 2016 +0100
Refactor jpg2ff
Remove some kitchen sink comments (the jpg boilerplate is already
horrible enough) and flush the output buffer manually to detect write
errors.
Also improve error reporting.
diff --git a/jpg2ff.c b/jpg2ff.c
index 52b4928..acf66b3 100644
--- a/jpg2ff.c
+++ b/jpg2ff.c
_AT_@ -1,34 +1,22 @@
/* See LICENSE file for copyright and license details. */
#include <arpa/inet.h>
+
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-
#include <setjmp.h>
-#include <jpeglib.h>
-char *argv0;
-
-static jmp_buf setjmp_buffer;
+#include <jpeglib.h>
-static void
-usage(void)
-{
- fprintf(stderr, "usage: %s\n", argv0);
- exit(1);
-}
+static jmp_buf error_jump;
METHODDEF(void)
-if_jpeg_error(j_common_ptr cinfo)
+jpeg_error(j_common_ptr cinfo)
{
- /* Always display the message. */
- /* We could postpone this until after returning, if we chose. */
- (*cinfo->err->output_message) (cinfo);
-
- /* Return control to the setjmp point */
- longjmp(setjmp_buffer, 1);
+ (*cinfo->err->output_message)(cinfo);
+ longjmp(error_jump, 1);
}
int
_AT_@ -42,18 +30,16 @@ main(int argc, char *argv[])
int ret = 1;
JSAMPARRAY buffer; /* output row buffer */
- argv0 = argv[0];
- if (argc > 1)
- usage();
+ if (argc > 1) {
+ fprintf(stderr, "usage: %s\n", argv[0]);
+ return 1;
+ }
- /* load jpeg */
+ /* load jpg */
cinfo.err = jpeg_std_error(&jerr);
- jerr.error_exit = if_jpeg_error;
- /* Establish the setjmp return context for my_error_exit to use. */
- if (setjmp(setjmp_buffer)) {
- /* If we get here, the JPEG code has signaled an error.
- * We need to clean up the JPEG object, close the input file, and return. */
+ jerr.error_exit = jpeg_error;
+ if (setjmp(error_jump)) {
goto cleanup;
}
_AT_@ -64,23 +50,23 @@ main(int argc, char *argv[])
width = cinfo.image_width;
height = cinfo.image_height;
- /* change output for farbfeld */
- cinfo.output_components = 3; /* # of color components per pixel */
- cinfo.out_color_space = JCS_RGB; /* colorspace of input image */
+ /* set output format */
+ cinfo.output_components = 3; /* color components per pixel */
+ cinfo.out_color_space = JCS_RGB; /* input color space */
jpeg_start_decompress(&cinfo);
jpeg_row_len = width * cinfo.output_components;
- /* Make a one-row-high sample array that will go away when done with image */
- buffer = (*cinfo.mem->alloc_sarray)
- ((j_common_ptr) &cinfo, JPOOL_IMAGE, jpeg_row_len, 1);
- ff_row_len = strlen("RRGGBBAA") * width;
+ /* create output buffers */
+ buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr)&cinfo,
+ JPOOL_IMAGE, jpeg_row_len, 1);
+ ff_row_len = strlen("RGBA") * sizeof(uint16_t) * width;
if(!(ff_row = malloc(ff_row_len))) {
- fprintf(stderr, "Can't malloc\n");
+ fprintf(stderr, "%s: malloc: out of memory\n", argv[0]);
return 1;
}
- /* write header with big endian width and height-values */
+ /* write header */
fprintf(stdout, "farbfeld");
val_be = htonl(width);
fwrite(&val_be, sizeof(uint32_t), 1, stdout);
_AT_@ -91,7 +77,7 @@ main(int argc, char *argv[])
/* jpeg_read_scanlines expects an array of pointers to scanlines.
* Here the array is only one element long, but you could ask for
* more than one scanline at a time if that's more convenient. */
- (void)jpeg_read_scanlines(&cinfo, buffer, 1);
+ jpeg_read_scanlines(&cinfo, buffer, 1);
for(i = 0, dx = 0, sx = 0; i < width; i++, sx += 3, dx += 4) {
ff_row[dx] = htons(buffer[0][sx] * 257);
_AT_@ -102,13 +88,25 @@ main(int argc, char *argv[])
/* write data */
if (fwrite(ff_row, 1, ff_row_len, stdout) != ff_row_len) {
- fprintf(stderr, "fwrite() failed\n");
+ fprintf(stderr, "%s: fwrite: ");
+ perror(NULL);
goto cleanup;
}
}
jpeg_finish_decompress(&cinfo);
ret = 0;
+ /* flush output */
+ if (fflush(stdout)) {
+ fprintf(stderr, "%s: fflush stdout: ", argv[0]);
+ perror(NULL);
+ ret = 1;
+ }
+ if (fclose(stdout) && !ret) {
+ fprintf(stderr, "%s: fclose stdout: ", argv[0]);
+ perror(NULL);
+ ret = 1;
+ }
cleanup:
free(ff_row);
jpeg_destroy_decompress(&cinfo);
Received on Wed Jan 06 2016 - 12:33:12 CET