[hackers] [sbase] Audit cut(1) || FRIGN

[git]

commit 54ccc0ef9a664e28f73302d164859aeaeff4d2c9
Author: FRIGN <d...@frign.de>
Date:   Wed Mar 11 17:29:18 2015 +0100

    Audit cut(1)
    
    1) Add check to parselist() to warn about an empty list.
    2) Remove all "cut: "-prefixes from error-messages and other style
       changes.
    3) != -1 --> >= 0 and check for ferror on fp after getline.
    4) Update usage with argv0.
    5) argv-centric loop refactor
    6) Properly report exit-status.
    7) Add empty line before return.

diff --git a/cut.c b/cut.c
index d916cf4..92da563 100644
--- a/cut.c
+++ b/cut.c
@@ -50,6 +50,8 @@ parselist(char *str)
        size_t n = 1;
        Range *r;
 
+       if (!*str)
+               eprintf("empty list\n");
        for (s = str; *s; s++) {
                if (*s == ' ')
                        *s = ',';
@@ -62,7 +64,7 @@ parselist(char *str)
                r->max = (*s == '-') ? strtoul(s + 1, &s, 10) : r->min;
                r->next = NULL;
                if (!r->min || (r->max && r->max < r->min) || (*s && *s != ','))
-                       eprintf("cut: bad list value\n");
+                       eprintf("bad list value\n");
                insert(r++);
        }
 }
@@ -103,7 +105,7 @@ seek(const char *s, size_t pos, size_t *prev, size_t count)
 }
 
 static void
-cut(FILE *fp)
+cut(FILE *fp, char *fname)
 {
        static char *buf = NULL;
        static size_t size = 0;
@@ -112,7 +114,7 @@ cut(FILE *fp)
        ssize_t len;
        Range *r;
 
-       while ((len = getline(&buf, &size, fp)) != -1) {
+       while ((len = getline(&buf, &size, fp)) >= 0) {
                if (len && buf[len - 1] == '\n')
                        buf[len - 1] = '\0';
                if (mode == 'f' && !utfutf(buf, delim)) {
@@ -132,24 +134,28 @@ cut(FILE *fp)
                        n = seek(s, r->max + 1, &p, i);
                        i += (mode == 'f') ? delimlen : 1;
                        if (fwrite(s, 1, n, stdout) != n)
-                               eprintf("write error:");
+                               eprintf("fwrite <stdout>:");
                }
                putchar('\n');
        }
+       if (ferror(fp))
+               eprintf("getline %s:", fname);
 }
 
 static void
 usage(void)
 {
-       eprintf("usage: cut -b list [-n] [file ...]\n"
-               "       cut -c list [file ...]\n"
-               "       cut -f list [-d delim] [-s] [file ...]\n");
+       eprintf("usage: %s -b list [-n] [file ...]\n"
+               "       %s -c list [file ...]\n"
+               "       %s -f list [-d delim] [-s] [file ...]\n",
+               argv0, argv0, argv0);
 }
 
 int
 main(int argc, char *argv[])
 {
        FILE *fp;
+       int ret = 0;
 
        ARGBEGIN {
        case 'b':
@@ -161,7 +167,7 @@ main(int argc, char *argv[])
        case 'd':
                delim = EARGF(usage());
                if (!*delim)
-                       eprintf("cut: empty delimiter\n");
+                       eprintf("empty delimiter\n");
                delimlen = unescape(delim);
                break;
        case 'n':
@@ -176,19 +182,24 @@ main(int argc, char *argv[])
 
        if (!mode)
                usage();
+
        if (!argc)
-               cut(stdin);
-       else for (; argc--; argv++) {
-               if (!strcmp(*argv, "-"))
-                       cut(stdin);
-               else {
-                       if (!(fp = fopen(*argv, "r"))) {
-                               weprintf("fopen %s:", *argv);
-                               continue;
+               cut(stdin, "<stdin>");
+       else {
+               for (; *argv; argc--, argv++) {
+                       if (*argv[0] == '-' && !*argv[1]) {
+                               cut(stdin, "<stdin>");
+                       } else {
+                               if (!(fp = fopen(*argv, "r"))) {
+                                       weprintf("fopen %s:", *argv);
+                                       ret = 1;
+                                       continue;
+                               }
+                               cut(fp, *argv);
+                               fclose(fp);
                        }
-                       cut(fp);
-                       fclose(fp);
                }
        }
-       return 0;
+
+       return ret;
 }