term: term_init: add 'cwd' argument

This is used when spawning the slave, to set its current working
directory just before we exec() the client.

In a regular foot instance, we set the cwd from getcwd().

In a foot server instance, each connecting client sends its cwd to the
server, and we use that.

main.c

@@ -7,6 +7,7 @@
 #include <getopt.h>
 #include <signal.h>
 #include <errno.h>
+#include <unistd.h>
 
 #include <sys/sysinfo.h>
 
@@ -217,6 +218,16 @@ main(int argc, char *const *argv)
     struct server *server = NULL;
     struct shutdown_context shutdown_ctx = {.term = &term, .exit_code = EXIT_FAILURE};
 
+    char *cwd = NULL;
+    {
+        size_t buf_len = 1024;
+        do {
+            cwd = realloc(cwd, buf_len);
+            getcwd(cwd, buf_len);
+            buf_len *= 2;
+        } while (errno == ERANGE);
+    }
+
     if ((fdm = fdm_init()) == NULL)
         goto out;
 
@@ -224,9 +235,12 @@ main(int argc, char *const *argv)
         goto out;
 
     if (!as_server && (term = term_init(
-                           &conf, fdm, wayl, conf.term, "foot", argc, argv,
-                           &term_shutdown_cb, &shutdown_ctx)) == NULL)
+                           &conf, fdm, wayl, conf.term, "foot", cwd, argc, argv,
+                           &term_shutdown_cb, &shutdown_ctx)) == NULL) {
+        free(cwd);
         goto out;
+    }
+    free(cwd);
 
     if (as_server && (server = server_init(&conf, fdm, wayl)) == NULL)
         goto out;

server.c

@@ -220,7 +220,7 @@ 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,
-        "footclient", argc, argv, &term_shutdown_handler, client);
+        "footclient", cwd, argc, argv, &term_shutdown_handler, client);
 
     if (client->term == NULL) {
         LOG_ERR("failed to instantiate new terminal");

slave.c

@@ -69,7 +69,7 @@ err:
 }
 
 pid_t
-slave_spawn(int ptmx, int argc, char *const *argv,
+slave_spawn(int ptmx, int argc, const char *cwd, char *const *argv,
             const char *term_env, const char *conf_shell)
 {
     int fork_pipe[2];
@@ -90,6 +90,8 @@ slave_spawn(int ptmx, int argc, char *const *argv,
         /* Child */
         close(fork_pipe[0]);  /* Close read end */
 
+        chdir(cwd);
+
         /* Restore signals */
         const struct sigaction sa = {.sa_handler = SIG_DFL};
         if (sigaction(SIGINT, &sa, NULL) < 0 ||

slave.h

@@ -4,4 +4,5 @@
 #include <sys/types.h>
 
 pid_t slave_spawn(
-    int ptmx, int argc, char *const *argv, const char *term_env, const char *conf_shell);
+    int ptmx, int argc, const char *cwd, char *const *argv, const char *term_env,
+    const char *conf_shell);

terminal.c

@@ -465,7 +465,8 @@ 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, const char *foot_exe, int argc, char *const *argv,
+          const char *term_env, const char *foot_exe, const char *cwd,
+          int argc, char *const *argv,
           void (*shutdown_cb)(void *data, int exit_code), void *shutdown_data)
 {
     int ptmx = -1;
@@ -601,18 +602,9 @@ 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),
-        .cwd = NULL,
+        .cwd = strdup(cwd),
     };
 
-    {
-        size_t buf_len = 1024;
-        do {
-            term->cwd = realloc(term->cwd, buf_len);
-            getcwd(term->cwd, buf_len);
-            buf_len *= 2;
-        } while (errno == ERANGE);
-    }
-
     initialize_color_cube(term);
     if (!initialize_render_workers(term))
         goto err;
@@ -626,7 +618,7 @@ term_init(const struct config *conf, struct fdm *fdm, struct wayland *wayl,
     LOG_INFO("cell width=%d, height=%d", term->cell_width, term->cell_height);
 
     /* Start the slave/client */
-    if ((term->slave = slave_spawn(term->ptmx, argc, argv, term_env, conf->shell)) == -1)
+    if ((term->slave = slave_spawn(term->ptmx, argc, term->cwd, argv, term_env, conf->shell)) == -1)
         goto err;
 
     /* Initiailze the Wayland window backend */

terminal.h

@@ -322,7 +322,8 @@ struct terminal {
 struct config;
 struct terminal *term_init(
     const struct config *conf, struct fdm *fdm, struct wayland *wayl,
-    const char *term_env, const char *foot_exe, int argc, char *const *argv,
+    const char *term_env, const char *foot_exe, const char *cwd,
+    int argc, char *const *argv,
     void (*shutdown_cb)(void *data, int exit_code), void *shutdown_data);
 
 bool term_shutdown(struct terminal *term);