[src/trunk]: src/sbin/fdisk instead of using ugly -1's make args optional

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/209163eacb00
branches:  trunk
changeset: 328446:209163eacb00
user:      christos <christos%NetBSD.org@localhost>
date:      Thu Apr 03 17:07:11 2014 +0000

description:
instead of using ugly -1's make args optional

diffstat:

 sbin/fdisk/fdisk.c |  89 +++++++++++++++++++++++++++++++++++++++++++----------
 1 files changed, 72 insertions(+), 17 deletions(-)

diffs (139 lines):

diff -r 3212889828f0 -r 209163eacb00 sbin/fdisk/fdisk.c
--- a/sbin/fdisk/fdisk.c        Thu Apr 03 17:07:07 2014 +0000
+++ b/sbin/fdisk/fdisk.c        Thu Apr 03 17:07:11 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fdisk.c,v 1.148 2014/04/01 19:08:48 christos Exp $ */
+/*     $NetBSD: fdisk.c,v 1.149 2014/04/03 17:07:11 christos Exp $ */
 
 /*
  * Mach Operating System
@@ -39,7 +39,7 @@
 #include <sys/cdefs.h>
 
 #ifndef lint
-__RCSID("$NetBSD: fdisk.c,v 1.148 2014/04/01 19:08:48 christos Exp $");
+__RCSID("$NetBSD: fdisk.c,v 1.149 2014/04/03 17:07:11 christos Exp $");
 #endif /* not lint */
 
 #define MBRPTYPENAMES
@@ -321,6 +321,66 @@
 #endif /* HAVE_NBTOOL_CONFIG_H */
 }
 
+static int
+getnum(const char *str, int *num)
+{
+       char *e;
+       long l;
+
+       errno = 0;
+       l = strtol(str, &e, 0);
+       if (str[0] == '\0' || *e != '\0')
+               return -1;
+       if (errno == ERANGE && (l == LONG_MAX || l == LONG_MIN))
+               return -1;
+       /* XXX: truncation */
+       *num = (int)l;
+       return 0;
+}
+
+/* [<sysid>][/[<start>][/[<size>][/[<bootmenu>]]]] */
+static int
+parse_s(char *arg, int *csysid, unsigned *cstart, unsigned *csize,
+    char **cbootmenu)
+{
+       char *ptr;
+       int num;
+
+       if ((ptr = strchr(arg, '/')) != NULL)
+               *ptr++ = '\0';
+
+       if (*arg) {
+               if (getnum(arg, &num) == -1)
+                       return -1;
+               *csysid = num;
+       }
+       if (ptr == NULL)
+               return 0;
+
+       arg = ptr;
+       if ((ptr = strchr(arg, '/')) != NULL)
+               *ptr++ = '\0';
+       if (*arg) {
+               if (getnum(arg, &num) == -1)
+                       return -1;
+               *cstart = num;
+       }
+       if (ptr == NULL)
+               return 0;
+
+       arg = ptr;
+       if ((ptr = strchr(arg, '/')) != NULL)
+               *ptr++ = '\0';
+       if (*arg) {
+               if (getnum(arg, &num) == -1)
+                       return -1;
+               *csize = num;
+       }
+       if (ptr != NULL && *ptr)
+               *cbootmenu = ptr;
+       return 0;
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -331,8 +391,8 @@
        int n;
 #ifdef BOOTSEL
        daddr_t default_ptn;            /* start sector of default ptn */
+#endif
        char *cbootmenu = 0;
-#endif
 
        int csysid;     /* For the s_flag. */
        unsigned int cstart, csize;
@@ -340,7 +400,8 @@
        i_flag = B_flag = 0;
        v_flag = 0;
        E_flag = 0;
-       csysid = cstart = csize = 0;
+       csysid = -1;
+       cstart = csize = ~0;
        while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
                switch (ch) {
                case '0':
@@ -397,18 +458,12 @@
                        break;
                case 's':       /* Partition details */
                        s_flag = 1;
-                       if (sscanf(optarg, "%d/%u/%u%n", &csysid, &cstart,
-                           &csize, &n) == 3) {
-                               if (optarg[n] == 0)
-                                       break;
-#ifdef BOOTSEL
-                               if (optarg[n] == '/') {
-                                       cbootmenu = optarg + n + 1;
-                                       break;
-                               }
-#endif
-                       }
-                       errx(1, "Bad argument to the -s flag.");
+
+                       if (parse_s(optarg, &csysid, &cstart, &csize,
+                           &cbootmenu) == -1)
+                               errx(1, "Bad argument to the -s flag.");
+                       printf("%d %d %d %s\n", csysid, cstart, csize, cbootmenu);
+                       exit(0);
                        break;
                case 'b':       /* BIOS geometry */
                        b_flag = 1;
@@ -621,7 +676,7 @@
                "[-A ptn_alignment[/ptn_0_offset]] \\\n"
                "%*s[-b cylinders/heads/sectors] \\\n"
                "%*s[-0123 | -E num "
-               "[-s id/start/size[/bootmenu]]] \\\n"
+               "[-s [id][/[start][/[size][/bootmenu]]]] \\\n"
                "%*s[-t disktab] [-T disktype] \\\n"
                "%*s[-c bootcode] "
                "[-r|-w file] [device]\n"