curl --head now reports info "headers" on file:// URLs as well

CHANGES

@@ -7,6 +7,12 @@
                                   Changelog
 
 
+Daniel (30 October)
+- David Hull made libcurl deal with NOBODY and HEADER for file:// the same way
+  it already does for FTP: it provides HTTP-looking headers that provide info
+  only about the file, without doing the actual transfer. The curl tool then
+  lets --head do this.
+
 Daniel (29 October)
 - runtests.pl now checks for and use valgrind if present. It will redirect the
   valgrind results in log/valgrind[num] but it currently doesn't scan that

docs/curl.1

@@ -367,10 +367,11 @@ name, IP address or host name. An example could look like:
 
 If this option is used several times, the last one will be used.
 .IP "-I/--head"
-(HTTP/FTP)
+(HTTP/FTP/FILE)
 Fetch the HTTP-header only! HTTP-servers feature the command HEAD
 which this uses to get nothing but the header of a document. When used
-on a FTP file, curl displays the file size only.
+on a FTP or FILE file, curl displays the file size and last modification
+time only.
 
 If this option is used twice, the second will again disable header only.
 .IP "-j/--junk-session-cookies"

lib/file.c

@@ -163,7 +163,8 @@ CURLcode Curl_file(struct connectdata *conn)
   */
   CURLcode res = CURLE_OK;
   struct stat statbuf;
-  double expected_size=-1;
+  unsigned long expected_size=0;
+  bool fstated=FALSE;
   ssize_t nread;
   struct SessionHandle *data = conn->data;
   char *buf = data->state.buffer;
@@ -178,25 +179,59 @@ CURLcode Curl_file(struct connectdata *conn)
 /*VMS?? -- This only works reliable for STREAMLF files */
   if( -1 != fstat(fd, &statbuf)) {
     /* we could stat it, then read out the size */
-    expected_size = (double)statbuf.st_size;
+    expected_size = statbuf.st_size;
+    fstated = TRUE;
+  }
+
+  /* If we have selected NOBODY and HEADER, it means that we only want file
+     information. Which for FILE can't be much more than the file size and
+     date. */
+  if(data->set.no_body && data->set.include_header && fstated) {
+    CURLcode result;
+    sprintf(buf, "Content-Length: %lu\r\n", expected_size);
+    result = Curl_client_write(data, CLIENTWRITE_BOTH, buf, 0);
+    if(result)
+      return result;
+
+    sprintf(buf, "Accept-ranges: bytes\r\n");
+    result = Curl_client_write(data, CLIENTWRITE_BOTH, buf, 0);
+    if(result)
+      return result;
+
+#ifdef HAVE_STRFTIME
+    if(fstated) {
+      struct tm *tm;
+#ifdef HAVE_LOCALTIME_R
+      struct tm buffer;
+      tm = (struct tm *)localtime_r((time_t *)&statbuf.st_mtime, &buffer);
+#else
+      tm = localtime((time_t *)&statbuf.st_mtime);
+#endif
+      /* format: "Tue, 15 Nov 1994 12:45:26 GMT" */
+      strftime(buf, BUFSIZE-1, "Last-Modified: %a, %d %b %Y %H:%M:%S GMT\r\n",
+               tm);
+      result = Curl_client_write(data, CLIENTWRITE_BOTH, buf, 0);
+    }
+#endif
+    return result;
   }
 
   /* Added by Dolbneff A.V & Spiridonoff A.V */
-  if (conn->resume_from <= expected_size)
+  if (conn->resume_from <= (long)expected_size)
     expected_size -= conn->resume_from;
   else
     /* Is this error code suitable in such situation? */
     return CURLE_FTP_BAD_DOWNLOAD_RESUME;
 
-  if (expected_size == 0)
+  if (fstated && (expected_size == 0))
     return CURLE_OK;
 
   /* The following is a shortcut implementation of file reading
      this is both more efficient than the former call to download() and
      it avoids problems with select() and recv() on file descriptors
      in Winsock */
-  if(expected_size != -1)
+  if(fstated)
-    Curl_pgrsSetDownloadSize(data, expected_size);
+    Curl_pgrsSetDownloadSize(data, (double)expected_size);
 
   if(conn->resume_from)
     /* Added by Dolbneff A.V & Spiridonoff A.V */