cgi-fcgi-interp: wip check_garbage

[chiark-utils.git] / cprogs / cgi-fcgi-interp.c

diff --git a/cprogs/cgi-fcgi-interp.c b/cprogs/cgi-fcgi-interp.c
index d2681cfc861a068cd5cbe4d8e7003f7c466c23c0..c08ba9da457d0e153bf52c2c04c1121487c2235e 100644 (file)
--- a/cprogs/cgi-fcgi-interp.c
+++ b/cprogs/cgi-fcgi-interp.c
@@ -2,7 +2,28 @@
  * "Interpreter" that you can put in #! like this
  *   #!/usr/bin/cgi-fcgi-interp [<options>] <interpreter>
  *   #!/usr/bin/cgi-fcgi-interp [<options>],<interpreter>
+ */
+/*
+ * cgi-fcgi-interp.[ch] - C helpers common to the whole of chiark-utils
+ *
+ * Copyright 2016 Ian Jackson
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
  *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this file; if not, consult the Free Software
+ * Foundation's website at www.fsf.org, or the GNU Project website at
+ * www.gnu.org.
+ */
+/*
  * The result is a program which looks, when executed via the #!
  * line, like a CGI program.  But the script inside will be executed
  * via <interpreter> in an fcgi context.
@@ -66,8 +87,8 @@
  *  - check for and maybe create <base>
  *  - stat and lstat the <script>
  *  - stat the socket and check its timestamp
- *       if it is too hold, rename it to g<inum> (where
- *       <inum> is in decimal)
+ *       if it is too old, rename it to g<inum>.<pid> (where
+ *       <inum> and <pid> are in decimal)
  *       and run garbage collection
  *  - run  cgi-fcgi -connect SOCKET SCRIPT
  */
@@ -139,7 +160,7 @@ static const struct cmdinfo cmdinfos[]= {
 };
 
 static uid_t us;
-static const char *run_base, *command, *socket_path;
+static const char *run_base, *script, *socket_path;
 
 static bool find_run_base_var_run(void) {
   struct stat stab;
@@ -207,7 +228,7 @@ static void find_socket_path(void) {
   if (!ident) {
     if (maxidentlen < MINHEXHASH)
       errx(127,"base directory `%s'"
-          " leaves only %d characters for command name hash"
+          " leaves only %d characters for id hash"
           " which is too little (<%d)",
           run_base, maxidentlen, MINHEXHASH);
 
@@ -219,7 +240,7 @@ static void find_socket_path(void) {
 
     sha256_init(&sc);
     sha256_update(&sc,strlen(interp)+1,interp);
-    sha256_update(&sc,strlen(command)+1,command);
+    sha256_update(&sc,strlen(script)+1,script);
     sha256_digest(&sc,sizeof(bbuf),bbuf);
 
     for (i=0; i<identlen; i += 2)
@@ -243,10 +264,17 @@ static void find_socket_path(void) {
   socket_path = m_asprintf("%s/g%s",run_base,ident);
 }  
 
+static bool stab_isnewer(const struct stat *a, const struct stat *b) {
+  return 0;
+}
+
 static bool check_garbage(void) {
-  struct stat sock_stab, cmd_stab;
+  struct stat sock_stab, script_stab;
   int r;
 
+  r = lstat(script, &script_stab);
+  if (r) err(127,"lstat script (%s)",script);
+
   r = lstat(socket_path, &sock_stab);
   if (r) {
     if ((errno == ENOENT))
@@ -254,8 +282,16 @@ static bool check_garbage(void) {
     err(127,"stat socket (%s)",socket_path);
   }
 
-  r = lstat(command, &cmd_stab);
-  if (r) err(127,"lstat command (%s)",command);
+  if (stab_isnewer(&script_stab, &sock_stab))
+    return 1;
+
+  if (S_ISLNK(script_stab.st_mode)) {
+    r = stat(script, &script_stab);
+    if (r) err(127,"stat script (%s0",script);
+
+    if (stab_isnewer(&script_stab, &sock_stab))
+      return 1;
+  }
 
   return 0;
 }
@@ -304,8 +340,8 @@ int main(int argc, const char *const *argv) {
     shbang_opts(&argv, cmdinfos);
   }
 
-  command = *argv++;
-  if (!command) errx(127,"need command argument");
+  script = *argv++;
+  if (!script) errx(127,"need script argument");
   if (*argv) errx(127,"too many arguments");
 
   find_socket_path();
@@ -315,7 +351,7 @@ int main(int argc, const char *const *argv) {
   if (debugmode) {
     printf("socket: %s\n",socket_path);
     printf("interp: %s\n",interp);
-    printf("command: %s\n",command);
+    printf("script: %s\n",script);
   }
 
   exit(0);