urlencode.c

   1 #include <stdio.h>
   2 #include <ctype.h>
   3 #include "grow.h"
   4 #include "urlencode.h"
   5
   6
   7
   8 static inline unsigned char nib2hex(int c)
   9 {
  10         return (c>=10 ? c+'a'-10 : c + '0');
  11 }
  12
  13 static inline unsigned int hex2nib(unsigned char c)
  14 {
  15         if (isdigit(c))
  16                 return c - '0';
  17         if (c >= 'a' && c <= 'f')
  18                 return c - 'a' + 10;
  19         if (c >= 'A' && c <= 'F')
  20                 return c - 'A' + 10;
  21         return 0;
  22 }
  23
  24
  25 void path_encode(struct grow *g, const char *path)
  26 {
  27         unsigned char c;
  28         char buf[3];
  29
  30         buf[0] = '%';
  31
  32         while ((c = *path++)) {
  33                 if (isalnum(c) || c == '_' || c == '/' || c == '.') {
  34                         grow_put(g, c);
  35                 } else {
  36                         buf[1] = nib2hex(c>>4);
  37                         buf[2] = nib2hex(c&15);
  38                         grow_append(g, buf, 3);
  39                 }
  40         }
  41 }
  42
  43 void path_decode(struct grow *g, const char *path)
  44 {
  45         unsigned char c, d;
  46
  47         while ((c = *path++)) {
  48                 if (c == '%') {
  49                         d = hex2nib(*path++) << 4;
  50                         d += hex2nib(*path++);
  51                         grow_put(g, d);
  52                 } else if (c == '&' && !strncasecmp(path, "amp;", 4)) {
  53                         grow_put(g, '&');
  54                         path += 4;
  55 /*              } else if (c == '+') { */
  56 /*                      grow_put(g, ' '); */
  57                 } else {
  58                         grow_put(g, c);
  59                 }
  60         }
  61 }
  62
  63 #ifdef EMO
  64
  65 struct grow g = GROW_INIT, h = GROW_INIT;
  66
  67 int main(int argc, char *argv[])
  68 {
  69         path_encode(&g, argv[1]);
  70         path_decode(&h, argv[2]);
  71         grow_put(&g, 0);
  72         grow_put(&h, 0);
  73
  74         printf("'%s' '%s'\n", g.arr, h.arr);
  75 }
  76
  77 #endif
  78
  79 #ifdef MAIN
  80 struct grow g = GROW_INIT, h = GROW_INIT;
  81
  82 int main(int argc, char *argv[])
  83 {
  84         char *p=argv[1], *r=argv[2];
  85         char *pfx=argv[3];
  86         if (argc < 4) {
  87                 printf("usage: %s <http_root> <path> <prefix>\n", argv[0]);
  88                 return 1;
  89         }
  90         while (*p == *r) {
  91                 p++;
  92                 r++;
  93         }
  94         while (*r == '/')
  95                 r++;
  96
  97         grow_puts(&g, pfx);
  98         if (pfx[strlen(pfx)-1] != '/')
  99                 grow_put(&g, '/');
 100         path_encode(&g, r);
 101
 102         printf("%s\n", grow_cstr(&g));
 103         return 0;
 104 }
 105
 106 #endif