[Olsr-dev] [PATCH v1 8/8] txtinfo: bring over proper http header support from jsoninfo

[Ferry Huberts]

From: Ferry Huberts <(spam-protected)>

Signed-off-by: Ferry Huberts <(spam-protected)>
---
 lib/txtinfo/src/olsrd_txtinfo.c | 73 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 70 insertions(+), 3 deletions(-)

diff --git a/lib/txtinfo/src/olsrd_txtinfo.c b/lib/txtinfo/src/olsrd_txtinfo.c
index 1c3e860..833a012 100644
--- a/lib/txtinfo/src/olsrd_txtinfo.c
+++ b/lib/txtinfo/src/olsrd_txtinfo.c
@@ -94,6 +94,9 @@
 
 static int ipc_socket;
 
+/* Response types */
+#define HTTP_200 "HTTP/1.1 200 OK"
+
 /* IPC initialization function */
 static int plugin_ipc_init(void);
 
@@ -136,6 +139,63 @@ static int outbuffer_count = 0;
 
 static struct timer_entry *writetimer_entry;
 
+static void build_http_header(const char *status, const char *mime, struct autobuf *abuf, int *contentLengthPlaceholderStart) {
+  /* Status */
+  abuf_appendf(abuf, "%s\r\n", status);
+
+  /* Date */
+  {
+    time_t currtime;
+    char buf[128];
+
+    time(&currtime);
+    if (strftime(buf, sizeof(buf), "Date: %a, %d %b %Y %H:%M:%S GMT\r\n", gmtime(&currtime))) {
+      abuf_puts(abuf, buf);
+    }
+  }
+
+  /* Server version */
+  abuf_puts(abuf, "Server: OLSRD "PLUGIN_NAME"\r\n");
+
+  /* connection-type */
+  abuf_puts(abuf, "Connection: close\r\n");
+
+  /* MIME type */
+  if (mime != NULL) {
+    abuf_appendf(abuf, "Content-Type: %s\r\n", mime);
+  }
+
+  /* CORS data */
+  /* No needs to be strict here, access control is based on source IP */
+  abuf_puts(abuf, "Access-Control-Allow-Origin: *\r\n");
+  abuf_puts(abuf, "Access-Control-Allow-Methods: GET, POST, OPTIONS\r\n");
+  abuf_puts(abuf, "Access-Control-Allow-Headers: Accept, Origin, X-Requested-With\r\n");
+  abuf_puts(abuf, "Access-Control-Max-Age: 1728000\r\n");
+
+  /* Content length */
+  abuf_puts(abuf, "Content-Length: ");
+  *contentLengthPlaceholderStart = abuf->len;
+  abuf_puts(abuf, "            "); /* 12 spaces reserved for the length (max. 1TB-1), to be filled at the end */
+  abuf_puts(abuf, "\r\n");
+
+  /* Cache-control
+   * No caching dynamic pages
+   */
+  abuf_puts(abuf, "Cache-Control: no-cache\r\n");
+
+  /* End header */
+  abuf_puts(abuf, "\r\n");
+}
+
+static void http_header_adjust_content_length(struct autobuf *abuf, int contentLengthPlaceholderStart, int contentLength) {
+  char buf[12 + 1]; /* size must match to number of spaces used (+1 for the terminating byte) */
+
+  memset(buf, 0, sizeof(buf));
+  snprintf(buf, sizeof(buf), "%d", contentLength);
+  buf[sizeof(buf) - 1] = '\0';
+  memcpy(&abuf->buf[contentLengthPlaceholderStart], buf, strlen(buf));
+}
+
 /**
  *Do initialization here
  *
@@ -794,12 +854,15 @@ static void info_write_data(void *foo __attribute__ ((unused))) {
 static void send_info(unsigned int send_what, int the_socket) {
   struct autobuf abuf;
 
+  const char *content_type = "text/plain; charset=utf-8";
+  int contentLengthPlaceholderStart = 0;
+  int headerLength = 0;
+
   abuf_init(&abuf, 2 * 4096);
 
-  /* Print minimal http header */
   if (http_headers) {
-    abuf_puts(&abuf, "HTTP/1.1 200 OK\r\n");
-    abuf_puts(&abuf, "Content-Type: text/plain; charset=utf-8\r\n\r\n");
+    build_http_header(HTTP_200, content_type, &abuf, &contentLengthPlaceholderStart);
+    headerLength = abuf.len;
   }
 
   /* Print tables to IPC socket */
@@ -831,6 +894,10 @@ static void send_info(unsigned int send_what, int the_socket) {
   if (send_what & SIW_OLSRD_CONF)
     ipc_print_olsrd_conf(&abuf);
 
+  if (http_headers) {
+    http_header_adjust_content_length(&abuf, contentLengthPlaceholderStart, abuf.len - headerLength);
+  }
+
   /* avoid a memcpy: just move the abuf.buf pointer and clear abuf */
   outbuffer[outbuffer_count] = abuf.buf;
   outbuffer_size[outbuffer_count] = abuf.len;
-- 
2.5.0