term: term_spawn_new(): new function, spawns a new foot/footclient process

Bind ctrl+shift+return to it

input.c

@@ -282,6 +282,11 @@ keyboard_key(void *data, struct wl_keyboard *wl_keyboard, uint32_t serial,
             search_begin(term);
             goto maybe_repeat;
         }
+
+        else if (sym == XKB_KEY_Return) {
+            term_spawn_new(term);
+            goto maybe_repeat;
+        }
     }
 
 

main.c

@@ -223,8 +223,9 @@ main(int argc, char *const *argv)
     if ((wayl = wayl_init(fdm)) == NULL)
         goto out;
 
-    if (!as_server && (term = term_init(&conf, fdm, wayl, conf.term, argc, argv,
-                                        &term_shutdown_cb, &shutdown_ctx)) == NULL)
+    if (!as_server && (term = term_init(
+                           &conf, fdm, wayl, conf.term, prog_name, argc, argv,
+                           &term_shutdown_cb, &shutdown_ctx)) == NULL)
         goto out;
 
     if (as_server && (server = server_init(&conf, fdm, wayl)) == NULL)

server.c

@@ -213,7 +213,7 @@ fdm_client(struct fdm *fdm, int fd, int events, void *data)
     client->term = term_init(
         server->conf, server->fdm, server->wayl,
         strlen(term_env) > 0 ? term_env : server->conf->term,
-        argc, argv, &term_shutdown_handler, client);
+        "footclient" /* TODO */, argc, argv, &term_shutdown_handler, client);
 
     if (client->term == NULL) {
         LOG_ERR("failed to instantiate new terminal");

slave.c

@@ -64,6 +64,7 @@ err:
         close(pts);
     if (ptmx != -1)
         close(ptmx);
+    close(err_fd);
     _exit(errno);
 }
 

terminal.c

@@ -465,7 +465,7 @@ initialize_fonts(struct terminal *term, const struct config *conf)
 
 struct terminal *
 term_init(const struct config *conf, struct fdm *fdm, struct wayland *wayl,
-          const char *term_env, int argc, char *const *argv,
+          const char *term_env, const char *foot_exe, int argc, char *const *argv,
           void (*shutdown_cb)(void *data, int exit_code), void *shutdown_data)
 {
     int ptmx = -1;
@@ -600,6 +600,7 @@ term_init(const struct config *conf, struct fdm *fdm, struct wayland *wayl,
         },
         .shutdown_cb = shutdown_cb,
         .shutdown_data = shutdown_data,
+        .foot_exe = strdup(foot_exe),
     };
 
     initialize_color_cube(term);
@@ -830,6 +831,7 @@ term_destroy(struct terminal *term)
         free(it->item.data);
     tll_free(term->ptmx_buffer);
     tll_free(term->tab_stops);
+    free(term->foot_exe);
 
     int ret = EXIT_SUCCESS;
 
@@ -1642,3 +1644,66 @@ term_flash(struct terminal *term, unsigned duration_ms)
         term->flash.active = true;
     }
 }
+
+bool
+term_spawn_new(const struct terminal *term)
+{
+    pid_t pid = fork();
+    if (pid < 0) {
+        LOG_ERRNO("failed to fork new terminal");
+        return false;
+    }
+
+    if (pid == 0) {
+        /* Child */
+        int pipe_fds[2] = {-1, -1};
+        if (pipe2(pipe_fds, O_CLOEXEC) < 0) {
+            LOG_ERRNO("failed to create pipe");
+            goto err;
+        }
+
+        /* Double fork */
+        pid_t pid2 = fork();
+        if (pid2 < 0) {
+            LOG_ERRNO("failed to double fork new terminal");
+            goto err;
+        }
+
+        if (pid2 == 0) {
+            /* Child */
+            close(pipe_fds[0]);
+            execl(term->foot_exe, term->foot_exe, NULL);
+            write(pipe_fds[1], &errno, sizeof(errno));
+            _exit(errno);
+        }
+
+        /* Parent */
+
+        close(pipe_fds[1]);
+
+        int _errno;
+        static_assert(sizeof(_errno) == sizeof(errno), "errno size mismatch");
+
+        ssize_t ret = read(pipe_fds[0], &_errno, sizeof(_errno));
+        close(pipe_fds[0]);
+
+        if (ret == 0)
+            _exit(0);
+        else if (ret < 0)
+            LOG_ERRNO("failed to read from pipe");
+        else {
+            LOG_ERRNO_P("%s: failed to spawn new terminal", _errno, term->foot_exe);
+            errno = _errno;
+            waitpid(pid2, NULL, 0);
+        }
+
+    err:
+        if (pipe_fds[0] != -1)
+            close(pipe_fds[0]);
+        _exit(errno);
+    }
+
+    int result;
+    waitpid(pid, &result, 0);
+    return WIFEXITED(result) && WEXITSTATUS(result) == 0;
+}

terminal.h

@@ -314,12 +314,14 @@ struct terminal {
     bool is_shutting_down;
     void (*shutdown_cb)(void *data, int exit_code);
     void *shutdown_data;
+
+    char *foot_exe;
 };
 
 struct config;
 struct terminal *term_init(
     const struct config *conf, struct fdm *fdm, struct wayland *wayl,
-    const char *term_env, int argc, char *const *argv,
+    const char *term_env, const char *foot_exe, int argc, char *const *argv,
     void (*shutdown_cb)(void *data, int exit_code), void *shutdown_data);
 
 bool term_shutdown(struct terminal *term);
@@ -379,3 +381,4 @@ void term_xcursor_update(struct terminal *term);
 
 void term_set_window_title(struct terminal *term, const char *title);
 void term_flash(struct terminal *term, unsigned duration_ms);
+bool term_spawn_new(const struct terminal *term);