file_util: implement urlencode_path() helper

[project/opkg-lede.git] / libopkg / file_util.c

diff --git a/libopkg/file_util.c b/libopkg/file_util.c
index 1f89541420afdf6092c04e098df68e0271144a92..14ca02e30a727f0daa00a4d23353c9af1e1bd98a 100644 (file)
--- a/libopkg/file_util.c
+++ b/libopkg/file_util.c
@@ -346,3 +346,63 @@ int rm_r(const char *path)
 
        return ret;
 }
+
+static int urlencode_is_specialchar(char c)
+{
+       switch (c) {
+       case ':':
+       case '?':
+       case '#':
+       case '[':
+       case ']':
+       case '@':
+       case '!':
+       case '$':
+       case '&':
+       case '\'':
+       case '(':
+       case ')':
+       case '*':
+       case '+':
+       case ',':
+       case ';':
+       case '=':
+       case '%':
+               return 1;
+
+       default:
+               return 0;
+       }
+}
+
+char *urlencode_path(const char *filename)
+{
+       static const char bin2hex[16] = {
+               '0', '1', '2', '3',
+               '4', '5', '6', '7',
+               '8', '9', 'a', 'b',
+               'c', 'd', 'e', 'f'
+       };
+
+       size_t len = 0;
+       const char *in;
+       char *copy, *out;
+
+       for (in = filename; *in != 0; in++)
+               len += urlencode_is_specialchar(*in) ? 3 : 1;
+
+       copy = xcalloc(1, len + 1);
+
+       for (in = filename, out = copy; *in != 0; in++) {
+               if (urlencode_is_specialchar(*in)) {
+                       *out++ = '%';
+                       *out++ = bin2hex[*in / 16];
+                       *out++ = bin2hex[*in % 16];
+               }
+               else {
+                       *out++ = *in;
+               }
+       }
+
+       return copy;
+}