implement wordexp. first try, may be buggy. intended to be safe.

[musl] / src / misc / wordexp.c

diff --git a/src/misc/wordexp.c b/src/misc/wordexp.c
new file mode 100644 (file)
index 0000000..b0d6846
--- /dev/null
+++ b/src/misc/wordexp.c
@@ -0,0 +1,128 @@
+#include <wordexp.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+static char *getword(FILE *f)
+{
+       char *s = 0;
+       return getdelim(&s, (size_t [1]){0}, 0, f) < 0 ? 0 : s;
+}
+
+int wordexp(const char *s, wordexp_t *we, int flags)
+{
+       size_t i, l, len;
+       int sq=0, dq=0;
+       size_t np=0;
+       char *cmd, *w, **tmp;
+       char *redir = (flags & WRDE_SHOWERR) ? "" : "2>/dev/null";
+       int err = 0, status;
+       FILE *f;
+       size_t wc = 0;
+       char **wv = 0;
+
+       if (flags & WRDE_REUSE) wordfree(we);
+
+       if (flags & WRDE_NOCMD) for (i=0; s[i]; i++) switch (s[i]) {
+       case '\\':
+               if (!sq) i++;
+               break;
+       case '\'':
+               if (!dq) sq^=1;
+               break;
+       case '"':
+               if (!sq) dq^=1;
+               break;
+       case '(':
+               if (np) {
+                       np++;
+                       break;
+               }
+       case ')':
+               if (np) {
+                       np--;
+                       break;
+               }
+       case '\n':
+       case '|':
+       case '&':
+       case ';':
+       case '<':
+       case '>':
+       case '{':
+       case '}':
+               if (!(sq|dq|np)) return WRDE_BADCHAR;
+               break;
+       case '$':
+               if (s[i+1]=='(' && s[i+2]=='(') {
+                       i += 2;
+                       np += 2;
+                       break;
+               } else if (s[i+1] != '(') break;
+       case '`':
+               if (sq) break;
+               return WRDE_CMDSUB;
+       }
+
+       if (flags & WRDE_APPEND) {
+               wc = we->we_wordc;
+               wv = we->we_wordv;
+       }
+
+       i = wc;
+       if (flags & WRDE_DOOFFS) {
+               if (we->we_offs > SIZE_MAX/sizeof(void *)/4)
+                       return WRDE_NOSPACE;
+               i += we->we_offs;
+       }
+
+       len = 50 + strlen(s);
+       cmd = malloc(len);
+       if (!cmd) return WRDE_NOSPACE;
+       snprintf(cmd, len, "printf %%s\\\\0 %s %s", s, redir);
+printf("{%s}\n", cmd);
+       f = popen(cmd, "r");
+       free(cmd);
+       if (!f) return WRDE_NOSPACE;
+
+       l = wv ? i+1 : 0;
+
+       while ((w = getword(f))) {
+               if (i+1 >= l) {
+                       l += l/2+10;
+                       tmp = realloc(wv, l*sizeof(char *));
+                       if (!tmp) break;
+                       wv = tmp;
+               }
+               wv[i++] = w;
+               wv[i] = 0;
+       }
+       if (!feof(f)) err = WRDE_NOSPACE;
+
+       status = pclose(f);
+       if (WEXITSTATUS(status)) {
+               if (!(flags & WRDE_APPEND)) {
+                       free(wv);
+                       return WRDE_SYNTAX;
+               } else if (wv==we->we_wordv) {
+                       return WRDE_SYNTAX;
+               }
+       }
+
+       we->we_wordv = wv;
+       we->we_wordc = i - we->we_offs;
+       return err;
+}
+
+void wordfree(wordexp_t *we)
+{
+       size_t i;
+       if (!we->we_wordv) return;
+       for (i=0; i<we->we_wordc; i++) free(we->we_wordv[we->we_offs+i]);
+       free(we->we_wordv);
+       we->we_wordv = 0;
+       we->we_wordc = 0;
+}