luad

commit a0a8bd0de4d55c3e0a8f419ef72023d0082c1bba
parent d5c2503150f2b65d666b93240346a5a3ba6901ff
Author: Daniel Barlow <dan@telent.net>
Date:   Tue, 19 May 2026 21:27:02 +0100

hardcode 3 fds

Diffstat:
M
luad.c
 | 
18
+++++++++---------

1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/luad.c b/luad.c
@@ -50,19 +50,19 @@ int open_socket(char * pathname) {
     return fd;
 }
 
-int * fds_from_msg(struct msghdr *msg, size_t peer_fds_count) {
-    int *peer_fds = (int *) calloc(peer_fds_count, sizeof(int));
+int * fds_from_msg(struct msghdr *msg) {
     // * there may be multiple SCM_RIGHTS messages
     // * we expect three fds
     // * if we get some number other than three, we should
     //   close them and return NULL
 
+    int *peer_fds = (int *) calloc(3, sizeof(int));
     for (struct cmsghdr* cmsg = CMSG_FIRSTHDR(msg);
          cmsg != NULL;
          cmsg = CMSG_NXTHDR(msg, cmsg)) {
         if(cmsg->cmsg_level == SOL_SOCKET &&
            cmsg->cmsg_type == SCM_RIGHTS) {
-            memcpy(peer_fds, CMSG_DATA(cmsg), peer_fds_count * sizeof(int));
+            memcpy(peer_fds, CMSG_DATA(cmsg), 3 * sizeof(int));
         }
     }
     return peer_fds;
@@ -70,14 +70,14 @@ int * fds_from_msg(struct msghdr *msg, size_t peer_fds_count) {
 
 int start_lua_child(lua_State *L,
                      char * command_line, int command_line_length,
-                     int * fds, int fds_count) {
+                     int * fds) {
     char * word = command_line;
     char * command_line_end = command_line + command_line_length;
     char * pathname = NULL;
     int i = 0;
 
     fflush(stdout); fflush(stderr);
-    for(int i=0; i < fds_count; i++) {
+    for(int i=0; i < 3; i++) {
         if(fds[i] > 0) dup2(fds[i], i);
     }
 
@@ -103,11 +103,11 @@ int start_lua_child(lua_State *L,
 
 pid_t fork_lua(lua_State *L,
               char * command_line, int command_line_length,
-               int * fds, int fds_count) {
+               int * fds) {
     pid_t pid = fork();
     if(pid == 0) {
         exit(start_lua_child(L, command_line, command_line_length,
-                             fds, fds_count));
+                             fds));
     } else if(pid > 0) {
         free(command_line);
         return pid;
@@ -218,14 +218,14 @@ int main(int argc, char **argv)
         if(pollfds[0].revents) {
             if(find_peer(0)) {
                 int len = recvmsg(socket, &msg , 0);
-                int *peer_fds = fds_from_msg(&msg, 5);
+                int *peer_fds = fds_from_msg(&msg);
                 char *argline = malloc(len);
                 if(! argline) {
                     die("malloc failed");
                 }
                 memmove(argline, buf, len);
 
-                pid_t child_pid = fork_lua(L, argline, len, peer_fds, 5);
+                pid_t child_pid = fork_lua(L, argline, len, peer_fds);
                 if(child_pid >= 0) {
                     register_peer(child_pid, &peer_addr, msg.msg_namelen);
                 }