diff options
| -rw-r--r-- | toys/cmp.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/toys/cmp.c b/toys/cmp.c new file mode 100644 index 00000000..f1e980e7 --- /dev/null +++ b/toys/cmp.c @@ -0,0 +1,97 @@ +/* vi: set sw=4 ts=4: + * + * cmp.c - Compare two files. + * + * Copyright 2012 Timothy Elliott <tle@holymonkey.com> + * + * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cmp.html + +USE_CMP(NEWTOY(cmp, "<2>2ls", TOYFLAG_USR|TOYFLAG_BIN)) + +config CMP + bool "cmp" + default y + help + usage: cmp [-l] [-s] FILE1 FILE2 + + Compare the contents of two files. + + -l show all differing bytes + -s silent +*/ + +#include "toys.h" + +#define FLAG_s 1 +#define FLAG_l 2 + +int get_fd(char *file) +{ + int fd; + + if (!strcmp(file,"-")) fd=0; + else if (0>(fd = open(file, O_RDONLY, 0))) { + perror_exit("%s", file); + } + return fd; +} + +void do_cmp(int fd1, int fd2, char *file1, char *file2, char *buf1, char *buf2, + size_t size) { + int i, len1, len2, min_len; + size_t byte_no = 1, line_no = 1; + + for (;;) { + len1 = read(fd1, buf1, size); + len2 = read(fd2, buf2, size); + + min_len = len1 < len2 ? len1 : len2; + for (i=0; i<min_len; i++) { + if (buf1[i] != buf2[i]) { + toys.exitval = 1; + if (toys.optflags & FLAG_l) { + printf("%d %o %o\n", byte_no, buf1[i], + buf2[i]); + } + else { + if (!(toys.optflags & FLAG_s)) { + printf("%s %s differ: char %d, line %d\n", + file1, file2, byte_no, + line_no); + } + return; + } + + } + byte_no++; + if (buf1[i] == '\n') line_no++; + } + if (len1 != len2) { + if (!(toys.optflags & FLAG_s)) { + fdprintf(2, "cmp: EOF on %s\n", + len1 < len2 ? file1 : file2); + } + toys.exitval = 1; + break; + } + if (len1 < 1) break; + } +} + +void cmp_main(void) +{ + char *file1 = toys.optargs[0]; + char *file2 = toys.optargs[1]; + int fd1, fd2, size=sizeof(toybuf); + char *toybuf2 = xmalloc(size); + + fd1 = get_fd(file1); + fd2 = get_fd(file2); + + do_cmp(fd1, fd2, file1, file2, toybuf, toybuf2, size); + + close(fd1); + close(fd2); + free(toybuf2); +} + |