First pass at a complete rewrite of string_to_mode(). (It compiled!)

diff --git a/lib/lib.c b/lib/lib.c
index a7eb65a..1b5488e 100644 (file)
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -916,113 +916,74 @@ char *num_to_sig(int sig)
 }
 
 
-/* mode parsing */
-
-mode_t apply_mode(int who, int how, int what, mode_t base)
+mode_t string_to_mode(char *modestr, mode_t mode)
 {
-       mode_t new_mode = 0, tmp_mode = 0, tmp_mask = 0;
-
-       if (!who) tmp_mask = 07777;
-       if (who & 0x01) { // u
-               if (what & 0x01) tmp_mode |= S_IXUSR;
-               if (what & 0x02) tmp_mode |= S_IWUSR;
-               if (what & 0x04) tmp_mode |= S_IRUSR;
-               if (what & 0x08) tmp_mode |= S_ISUID;
-               tmp_mask |= S_IRWXU;
-       }
-       if (who & 0x02) { // g
-               if (what & 0x01) tmp_mode |= S_IXGRP;
-               if (what & 0x02) tmp_mode |= S_IWUSR;
-               if (what & 0x04) tmp_mode |= S_IRUSR;
-               if (what & 0x08) tmp_mode |= S_ISGID;
-               tmp_mask |= S_IRWXG;
-       }
-       if (who & 0x04) { // o
-               if (what & 0x01) tmp_mode |= S_IXOTH;
-               if (what & 0x02) tmp_mode |= S_IWOTH;
-               if (what & 0x04) tmp_mode |= S_IROTH;
-               tmp_mask |= S_IRWXO;
+       char *whos = "ugoa", *hows = "=+-", *whats = "xwrstX", *whys = "ogu";
+       char *s, *str = modestr;
+
+       // Handle octal mode
+       if (isdigit(*str)) {
+               mode = strtol(str, &s, 8);
+               if (*s || (mode & ~(07777))) goto barf;
+
+               return mode;
        }
-       /* check sticky */
-       if (what & 0x10) tmp_mode |= S_ISVTX;
 
-       if (how == 1) new_mode = tmp_mode | (base & tmp_mask);
-       else if (how == 2) new_mode = base | tmp_mode;
-       else if (how == 3) new_mode = base & ~(tmp_mode);
+       // Gaze into the bin of permission...
+       for (;;) {
+               int i, j, dowho, dohow, dowhat;
 
-       return new_mode;
-}
+               dowho = dohow = dowhat = 0;
 
+               // Find the who, how, and what stanzas, in that order
+               while ((s = strchr(whos, *str))) {
+                       dowho |= 1<<(whos-s);
+                       str++;
+               }
+               if (!dowho) dowho = 8;
+               if (!(s = strchr(hows, *str))) goto barf;
+               dohow = *(str++);
+               if (!dohow) goto barf;
+               while ((s = strchr(whats, *str))) {
+                       dowhat |= 1<<(whats-s);
+                       str++;
+               }
 
-mode_t string_to_mode(char *mode_str, mode_t base)
-{
-       mode_t new_mode;
-       int what = 0;
-       int who = 0;
-       int how = 0;
-       char *p;
-       long tmp;
-       if (!mode_str)
-               return base;
-       if (isdigit(mode_str[0])) {
-               tmp = strtol(mode_str, &p, 8);
-               if (*p || tmp < 0 || (tmp & ~(07777))) return base;
-               new_mode = (mode_t) tmp;
-               return new_mode;
-       }
-       new_mode = base;
-       while (*mode_str) {
-               /* TODO: add support for permission copying */
-               switch(*mode_str) {
-               case ',':
-                       /* next command */
-                       new_mode = apply_mode(who, how, what, new_mode);
-                       who = 0;
-                       how = 0;
-                       what = 0;
-                       break;
-               case 'a':
-                       who = 0x01 | 0x02 | 0x04;
-                       break;
-               case 'u':
-                       who |= 0x01;
-                       break;
-               case 'g':
-                       who |= 0x02;
-                       break;
-               case 'o':
-                       who |= 0x04;
-                       break;
-               case 'r':
-                       what |= 0x04;
-                       break;
-               case 'w':
-                       what |= 0x02;
-                       break;
-               case 'x':
-                       what |= 0x01;
-                       break;
-               case 't':
-                       what |= 0x10;
-                       break;
-               case 's':
-                       what |= 0x08;
-                       break;
-               case '=':
-                       how = 1;
-                       break;
-               case '+':
-                       how = 2;
-                       break;
-               case '-':
-                       how = 3;
-                       break;
-               default:
-                       /* error case */
-                       return base;
+               // Convert X to x for directory or if already executable somewhere
+               if ((dowhat&32) &&  (S_ISDIR(mode) || (mode&0111))) dowhat |= 1;
+
+               // Copy mode from another category?
+               if (!dowhat && (s = strchr(whys, *str))) {
+                       dowhat = (mode>>(3*(s-str)))&7;
+                       str++;
+               }
+
+               // Are we ready to do a thing yet?
+               if (*str && *(str++) != ',') goto barf;
+
+               // Ok, apply the bits to the mode.
+               for (i=0; i<4; i++) {
+                       for (j=0; j<3; j++) {
+                               mode_t bit = 0;
+
+                               // Figure out new value at this location
+                               if (i == 3) {
+                               } else if (dowhat&(1<<j)) bit++;
+
+                               // When selection active, modify bit
+                               if (dowho&(8|(1<<i))) {
+                                       int where = 1<<((3*i)+j);
+
+                                       if (dohow == '=' || (bit && dohow == '-'))
+                                               mode &= ~where;
+                                       if (bit && dohow != '-') mode |= where;
+                               }
+                       }
                }
-               mode_str++;
+
+               if (!*str) break;
        }
-       new_mode = apply_mode(who, how, what, new_mode);
-       return new_mode;
+       return mode;
+barf:
+       error_exit("bad mode '%s'", modestr);
 }