diff options
Diffstat (limited to 'png2ff.c')
| -rw-r--r-- | png2ff.c | 66 |
1 files changed, 36 insertions, 30 deletions
@@ -2,39 +2,46 @@ #include <arpa/inet.h> #include <errno.h> -#include <setjmp.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <png.h> +static char *argv0; + +void +pngerr(png_structp png_struct_p, png_const_charp msg) +{ + fprintf(stderr, "%s: libpng: %s\n", argv0, msg); + exit(1); +} + int main(int argc, char *argv[]) { png_structp png_struct_p; png_infop png_info_p; png_bytepp png_row_p; - int depth, color, ret = 0; uint32_t width, height, png_row_len, tmp32, r, i; uint16_t tmp16; - if (argc > 1) { - fprintf(stderr, "usage: %s\n", argv[0]); + argv0 = argv[0], argc--, argv++; + + if (argc) { + fprintf(stderr, "usage: %s\n", argv0); return 1; } /* load png */ png_struct_p = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, - NULL, NULL); + pngerr, NULL); png_info_p = png_create_info_struct(png_struct_p); if (!png_struct_p || !png_info_p) { - fprintf(stderr, "%s: failed to initialize libpng\n", argv[0]); + fprintf(stderr, "%s: failed to initialize libpng\n", argv0); return 1; } - if (setjmp(png_jmpbuf(png_struct_p))) - return 1; png_init_io(png_struct_p, stdin); if (png_get_valid(png_struct_p, png_info_p, PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_struct_p); @@ -44,56 +51,55 @@ main(int argc, char *argv[]) png_set_packing(png_struct_p); png_read_png(png_struct_p, png_info_p, PNG_TRANSFORM_PACKING | PNG_TRANSFORM_EXPAND, NULL); - png_get_IHDR(png_struct_p, png_info_p, &width, &height, &depth, - &color, NULL, NULL, NULL); + width = png_get_image_width(png_struct_p, png_info_p); + height = png_get_image_height(png_struct_p, png_info_p); png_row_len = png_get_rowbytes(png_struct_p, png_info_p); png_row_p = png_get_rows(png_struct_p, png_info_p); /* write header */ fputs("farbfeld", stdout); tmp32 = htonl(width); - fwrite(&tmp32, sizeof(uint32_t), 1, stdout); + if (fwrite(&tmp32, sizeof(uint32_t), 1, stdout) != 1) + goto writerr; tmp32 = htonl(height); - fwrite(&tmp32, sizeof(uint32_t), 1, stdout); + if (fwrite(&tmp32, sizeof(uint32_t), 1, stdout) != 1) + goto writerr; /* write data */ - switch(depth) { + switch(png_get_bit_depth(png_struct_p, png_info_p)) { case 8: for (r = 0; r < height; ++r) { for (i = 0; i < png_row_len; i++) { /* ((2^16-1) / 255) == 257 */ tmp16 = htons(257 * png_row_p[r][i]); - fwrite(&tmp16, sizeof(uint16_t), 1, stdout); + if (fwrite(&tmp16, sizeof(uint16_t), 1, + stdout) != 1) + goto writerr; } } break; case 16: for (r = 0; r < height; ++r) { for (i = 0; i < png_row_len / 2; i++) { - tmp16 = *((uint16_t *) - (png_row_p[r] + 2 * i)); - fwrite(&tmp16, sizeof(uint16_t), 1, stdout); + tmp16 = *((uint16_t *)(png_row_p[r] + + 2 * i)); + if (fwrite(&tmp16, sizeof(uint16_t), 1, + stdout) != 1) + goto writerr; } } break; default: - fprintf(stderr, "%s: format error\n", argv[0]); + fprintf(stderr, "%s: invalid bit-depth\n", argv0); return 1; } png_destroy_read_struct(&png_struct_p, &png_info_p, NULL); - /* 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; - } + return 0; +writerr: + fprintf(stderr, "%s: fwrite: ", argv0); + perror(NULL); - return ret; + return 1; } |