1 files changed, 202 insertions, 0 deletions

diff --git a/xs_url.h b/xs_url.h
new file mode 100644
index 0000000..5fca5cb
--- /dev/null
+++ b/xs_url.h
@@ -0,0 +1,202 @@
+/* copyright (c) 2022 - 2023 grunfink et al. / MIT license */
+
+#ifndef _XS_URL_H
+
+#define _XS_URL_H
+
+xs_str *xs_url_dec(const char *str);
+xs_dict *xs_url_vars(const char *str);
+xs_dict *xs_multipart_form_data(const char *payload, int p_size, const char *header);
+
+
+#ifdef XS_IMPLEMENTATION
+
+xs_str *xs_url_dec(const char *str)
+/* decodes an URL */
+{
+    xs_str *s = xs_str_new(NULL);
+
+    while (*str) {
+        if (*str == '%') {
+            int i;
+
+            if (sscanf(str + 1, "%02x", &i) == 1) {
+                unsigned char uc = i;
+
+                s = xs_append_m(s, (char *)&uc, 1);
+                str += 2;
+            }
+        }
+        else
+        if (*str == '+')
+            s = xs_append_m(s, " ", 1);
+        else
+            s = xs_append_m(s, str, 1);
+
+        str++;
+    }
+
+    return s;
+}
+
+
+xs_dict *xs_url_vars(const char *str)
+/* parse url variables */
+{
+    xs_dict *vars;
+
+    vars = xs_dict_new();
+
+    if (str != NULL) {
+        /* split by arguments */
+        xs *args = xs_split(str, "&");
+
+        xs_list *l;
+        xs_val *v;
+
+        l = args;
+        while (xs_list_iter(&l, &v)) {
+            xs *kv = xs_split_n(v, "=", 2);
+
+            if (xs_list_len(kv) == 2) {
+                const char *key = xs_list_get(kv, 0);
+                const char *pv  = xs_dict_get(vars, key);
+
+                if (!xs_is_null(pv)) {
+                    /* there is a previous value: convert to a list and append */
+                    xs *vlist = NULL;
+                    if (xs_type(pv) == XSTYPE_LIST)
+                        vlist = xs_dup(pv);
+                    else {
+                        vlist = xs_list_new();
+                        vlist = xs_list_append(vlist, pv);
+                    }
+
+                    vlist = xs_list_append(vlist, xs_list_get(kv, 1));
+                    vars  = xs_dict_set(vars, key, vlist);
+                }
+                else {
+                    /* ends with []? force to always be a list */
+                    if (xs_endswith(key, "[]")) {
+                        xs *vlist = xs_list_new();
+                        vlist = xs_list_append(vlist, xs_list_get(kv, 1));
+                        vars = xs_dict_append(vars, key, vlist);
+                    }
+                    else
+                        vars = xs_dict_append(vars, key, xs_list_get(kv, 1));
+                }
+            }
+        }
+    }
+
+    return vars;
+}
+
+
+xs_dict *xs_multipart_form_data(const char *payload, int p_size, const char *header)
+/* parses a multipart/form-data payload */
+{
+    xs *boundary = NULL;
+    int offset = 0;
+    int bsz;
+    char *p;
+
+    /* build the boundary string */
+    {
+        xs *l1 = xs_split(header, "=");
+
+        if (xs_list_len(l1) != 2)
+            return NULL;
+
+        boundary = xs_fmt("--%s", xs_list_get(l1, 1));
+    }
+
+    bsz = strlen(boundary);
+
+    xs_dict *p_vars = xs_dict_new();
+
+    /* iterate searching the boundaries */
+    while ((p = xs_memmem(payload + offset, p_size - offset, boundary, bsz)) != NULL) {
+        xs *s1 = NULL;
+        xs *l1 = NULL;
+        char *vn = NULL;
+        char *fn = NULL;
+        char *q;
+        int po, ps;
+
+        /* final boundary? */
+        p += bsz;
+
+        if (p[0] == '-' && p[1] == '-')
+            break;
+
+        /* skip the \r\n */
+        p += 2;
+
+        /* now on a Content-Disposition... line; get it */
+        q = strchr(p, '\r');
+        s1 = xs_realloc(NULL, q - p + 1);
+        memcpy(s1, p, q - p);
+        s1[q - p] = '\0';
+
+        /* move on (over a \r\n) */
+        p = q;
+
+        /* split by " like a primitive man */
+        l1 = xs_split(s1, "\"");
+
+        /* get the variable name */
+        vn = xs_list_get(l1, 1);
+
+        /* is it an attached file? */
+        if (xs_list_len(l1) >= 4 && strcmp(xs_list_get(l1, 2), "; filename=") == 0) {
+            /* get the file name */
+            fn = xs_list_get(l1, 3);
+        }
+
+        /* find the start of the part content */
+        if ((p = xs_memmem(p, p_size - (p - payload), "\r\n\r\n", 4)) == NULL)
+            break;
+
+        p += 4;
+
+        /* find the next boundary */
+        if ((q = xs_memmem(p, p_size - (p - payload), boundary, bsz)) == NULL)
+            break;
+
+        po = p - payload;
+        ps = q - p - 2;     /* - 2 because the final \r\n */
+
+        /* is it a filename? */
+        if (fn != NULL) {
+            /* p_var value is a list */
+            xs *l1 = xs_list_new();
+            xs *vpo = xs_number_new(po);
+            xs *vps = xs_number_new(ps);
+
+            l1 = xs_list_append(l1, fn);
+            l1 = xs_list_append(l1, vpo);
+            l1 = xs_list_append(l1, vps);
+
+            p_vars = xs_dict_append(p_vars, vn, l1);
+        }
+        else {
+            /* regular variable; just copy */
+            xs *vc = xs_realloc(NULL, ps + 1);
+            memcpy(vc, payload + po, ps);
+            vc[ps] = '\0';
+
+            p_vars = xs_dict_append(p_vars, vn, vc);
+        }
+
+        /* move on */
+        offset = q - payload;
+    }
+
+    return p_vars;
+}
+
+
+#endif /* XS_IMPLEMENTATION */
+
+#endif /* XS_URL_H */