clean up

main/web_server.c

@@ -154,42 +154,49 @@ static void send_json(httpd_req_t *req, int status, const char *body)
 
 static char *url_decode(const char *src)
 {
-    if (src == NULL) {
-        return NULL;
-    }
-    size_t len = strlen(src);
-    if (len > HTTPD_BODY_MAX - 1) {
-        len = HTTPD_BODY_MAX - 1;
-    }
-    char *out = malloc(len + 1);
-    if (out == NULL) {
-        return NULL;
-    }
-    size_t o = 0;
-    for (size_t i = 0; i < len && src[i] != '\0'; i++) {
-        if (src[i] == '%' && i + 2 < len) {
-            int hi = src[i + 1] >= 'a' ? src[i + 1] - 'a' + 10
-                : src[i + 1] >= 'A' ? src[i + 1] - 'A' + 10
-                : src[i + 1] - '0';
-            int lo = src[i + 2] >= 'a' ? src[i + 2] - 'a' + 10
-                : src[i + 2] >= 'A' ? src[i + 2] - 'A' + 10
-                : src[i + 2] - '0';
-            if (hi < 0 || hi > 15 || lo < 0 || lo > 15) {
-                free(out);
-                return NULL;
-            }
-            out[o++] = (char)((hi << 4) | lo);
-            i += 2;
-        } else if (src[i] == '+') {
-            out[o++] = ' ';
+    if (!src) return NULL;
+    char *out = strdup(src);
+    if (!out) return NULL;
+    char *dst = out;
+    for (const char *s = src; *s; s++) {
+        if (*s == '%' && s[1] && s[2]) {
+            char hex[3] = { s[1], s[2], '\0' };
+            *dst++ = (char)strtol(hex, NULL, 16);
+            s += 2;
+        } else if (*s == '+') {
+            *dst++ = ' ';
         } else {
-            out[o++] = src[i];
+            *dst++ = *s;
         }
     }
-    out[o] = '\0';
+    *dst = '\0';
     return out;
 }
 
+static char *get_form_param(const char *form, const char *key)
+{
+    if (!form || !key) return NULL;
+    size_t klen = strlen(key);
+    const char *p = form;
+    while (p && *p) {
+        if (strncmp(p, key, klen) == 0 && p[klen] == '=') {
+            const char *val_start = p + klen + 1;
+            const char *val_end = strchr(val_start, '&');
+            size_t vlen = val_end ? (size_t)(val_end - val_start) : strlen(val_start);
+            char *raw = malloc(vlen + 1);
+            if (!raw) return NULL;
+            memcpy(raw, val_start, vlen);
+            raw[vlen] = '\0';
+            char *dec = url_decode(raw);
+            free(raw);
+            return dec;
+        }
+        p = strchr(p, '&');
+        if (p) p++;
+    }
+    return NULL;
+}
+
 /* ------------------------------------------------------------------ */
 /*  Endpoints                                                          */
 /* ------------------------------------------------------------------ */
@@ -234,22 +241,8 @@ static esp_err_t handle_bind(httpd_req_t *req)
     }
     form[got] = '\0';
 
-    char *uid = NULL;
-    char *name = NULL;
-    char *u = strstr(form, "uid=");
-    char *n = strstr(form, "name=");
-    if (u) {
-        char *end = strchr(u, '&');
-        if (end) *end = '\0';
-        uid = url_decode(u + 4);
-        if (end) *end = '&';
-    }
-    if (n) {
-        char *end = strchr(n, '&');
-        if (end) *end = '\0';
-        name = url_decode(n + 5);
-        if (end) *end = '&';
-    }
+    char *uid = get_form_param(form, "uid");
+    char *name = get_form_param(form, "name");
     free(form);
 
     if (uid) {
@@ -355,14 +348,7 @@ static esp_err_t handle_unbind(httpd_req_t *req)
     }
     form[got] = '\0';
 
-    char *uid = NULL;
-    char *u = strstr(form, "uid=");
-    if (u) {
-        char *end = strchr(u, '&');
-        if (end) *end = '\0';
-        uid = url_decode(u + 4);
-        if (end) *end = '&';
-    }
+    char *uid = get_form_param(form, "uid");
     free(form);
 
     if (uid) {