diff options
| -rw-r--r-- | coreutils/tac.c | 46 |
1 files changed, 35 insertions, 11 deletions
diff --git a/coreutils/tac.c b/coreutils/tac.c index b1b47302f..7951be255 100644 --- a/coreutils/tac.c +++ b/coreutils/tac.c @@ -20,12 +20,17 @@ /* This is a NOEXEC applet. Be very careful! */ +struct lstring { + int size; + char buf[]; +}; + int tac_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int tac_main(int argc, char **argv) { char **name; FILE *f; - char *line; + struct lstring *line = NULL; llist_t *list = NULL; int retval = EXIT_SUCCESS; @@ -38,6 +43,8 @@ int tac_main(int argc, char **argv) name++; do { + int ch, i; + name--; f = fopen_or_warn_stdin(*name); if (f == NULL) { @@ -45,14 +52,26 @@ int tac_main(int argc, char **argv) continue; } - errno = 0; - /* FIXME: NUL bytes are mishandled. */ - while ((line = xmalloc_fgets(f)) != NULL) - llist_add_to(&list, line); - - /* xmalloc_fgets uses getc and returns NULL on error or EOF. */ - /* It sets errno to ENOENT on EOF, but fopen_or_warn_stdin would */ - /* catch this error so we can filter it out here. */ + errno = i = 0; + do { + ch = fgetc(f); + if (ch != EOF) { + if (!(i & 0x7f)) + /* Grow on every 128th char */ + line = xrealloc(line, i + 0x7f + sizeof(int) + 1); + line->buf[i++] = ch; + } + if ((ch == '\n' || ch == EOF) && i) { + line = xrealloc(line, i + sizeof(int)); + line->size = i; + llist_add_to(&list, line); + line = NULL; + i = 0; + } + } while (ch != EOF); + /* fgetc sets errno to ENOENT on EOF, but */ + /* fopen_or_warn_stdin would catch this error */ + /* so we can filter it out here. */ if (errno && errno != ENOENT) { bb_simple_perror_msg(*name); retval = EXIT_FAILURE; @@ -60,8 +79,13 @@ int tac_main(int argc, char **argv) } while (name != argv); while (list) { - printf("%s", list->data); - list = list->link; + line = (struct lstring *)list->data; + xwrite(STDOUT_FILENO, line->buf, line->size); + if (ENABLE_FEATURE_CLEAN_UP) { + free(llist_pop(&list)); + } else { + list = list->link; + } } return retval; |