diff options
Diffstat (limited to 'splice.c')
| -rw-r--r-- | splice.c | 22 |
1 files changed, 10 insertions, 12 deletions
@@ -3,6 +3,8 @@ #include <stdint.h> #include <stdlib.h> +#define MIN(a, b) ((a) < (b) ? (a) : (b)) + int main(int argc, const char **argv) { @@ -14,7 +16,7 @@ main(int argc, const char **argv) int ret; if (argc < 3 || argc > 4) { - printf("USAGE: fwpatch MAIN START [END]\n"); + fprintf(stderr, "USAGE: splice MAIN START [END]\n"); return 0; } @@ -28,27 +30,23 @@ main(int argc, const char **argv) if (argc == 4) { end = strtoll(argv[3], &endc, 0); if (endc && *endc) err(1, "strtoll %s", argv[3]); - if (start >= end) errx(1, "invalid length"); + if (start >= end) errx(1, "invalid end"); } else { end = -1; } pos = 0; while (!feof(main_file) || !feof(stdin)) { - if (pos >= start && !feof(stdin)) { - nread = fread(buf, 1, BUFSIZ, stdin); + if (pos >= start && (pos < end || !feof(stdin))) { + if (feof(stdin)) errx(1, "input truncated"); + nreq = end >= 0 ? MIN(BUFSIZ, end - start) : BUFSIZ; + nread = fread(buf, 1, nreq, stdin); if (pos == start && end >= 0) - fseek(main_file, end, SEEK_CUR); + fseek(main_file, end, SEEK_SET); else if (end < 0) fseek(main_file, nread, SEEK_CUR); } else { - if (start > pos) { - nreq = start - pos; - if (nreq > BUFSIZ) - nreq = BUFSIZ; - } else { - nreq = BUFSIZ; - } + nreq = pos < start ? MIN(BUFSIZ, start - pos) : BUFSIZ; nread = fread(buf, 1, nreq, main_file); } if (fwrite(buf, 1, nread, stdout) != nread) |