Added namespace support to Horizon bootstrap msg parsing

photon/libc/sys/horizon/init.c

@@ -10,11 +10,18 @@
 #include <mio/fd.h>
 #include <mio/fs.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include "__init.h"
 #include "__heap.h"
 #include "__fio.h"
 
+/* maximum of 32 handles can be received sent as arguments */
+#define MAX_HANDLE_ARGS 32
+
+/* maximum size of bootstrap message that can be received */
+#define MAX_MSG_SIZE 0x2000
+
 #if 1
 #define dbg_log(...)
 #else
@@ -33,6 +40,7 @@ static void dbg_log(const char *format, ...)
 #endif
 
 static const char **environ = NULL;
+static char arg_msg_buf[MAX_MSG_SIZE];
 
 const char **__crt_environ()
 {
@@ -42,9 +50,19 @@ const char **__crt_environ()
 extern int main(int, const char **);
 extern void __crt_run_atexit();
 
-static void parse_args(
-        mx_bootstrap_msg_t *args, mx_handle_t *handles,
-        const char **argv, const char **envp, int hndc, mx_bootstrap_handle_t *handles_out)
+static void extract_arg_handles(mx_bootstrap_msg_t *args,
+        mx_handle_t *handles, int hndc, mx_bootstrap_handle_t *out)
+{
+    uint32_t *hent = (uint32_t *)((char *)args + args->handle_info_off);
+
+    for (int i = 0; i < hndc; i++) {
+        out[i].info = hent[i];
+        out[i].handle = handles[i];
+    }
+}
+
+static void parse_args(mx_bootstrap_msg_t *args,
+        const char **argv, const char **envp, const char **namep)
 {
     if (args->args_num > 0) {
         char *arg_buf = (char *)args + args->args_off;
@@ -63,7 +81,6 @@ static void parse_args(
         }
     }
 
-#if 0
     if (args->environ_num > 0) {
         char *env_buf = (char *)args + args->environ_off;
         int env_i = 0;
@@ -80,13 +97,22 @@ static void parse_args(
             }
         }
     }
-#endif
 
-    uint32_t *hent = (uint32_t *)((char *)args + args->handle_info_off);
+    if (args->names_num) {
+        char *name_buf = (char *)args + args->names_off;
+        int name_i = 0;
+        int name_off = 0;
 
-    for (int i = 0; i < hndc; i++) {
-        handles_out[i].info = hent[i];
-        handles_out[i].handle = handles[i];
+        for (int i = 0; ; i++) {
+            if (name_buf[i] == '\0') {
+                namep[name_i++] = name_buf + name_off;
+                name_off = i + 1;
+            }
+
+            if (name_i == (int)args->names_num) {
+                break;
+            }
+        }
     }
 }
 
@@ -193,49 +219,51 @@ int __crt_init(mx_handle_t bootstrap)
     mx_object_wait(bootstrap, MX_TUNNEL_READABLE, 0, &sig);
     if (!(sig & MX_TUNNEL_READABLE)) {
         dbg_log("no bootstrap message!\n");
+        return -1;
     }
 
     size_t msg_size = 0;
     size_t nr_handles = 0;
-    mx_status_t status = mx_tunnel_read(bootstrap, NULL, 0, NULL, 0, &msg_size, &nr_handles);
-    dbg_log("read bootstrap message\n");
 
-    if (status != MX_OK) {
-        /* TODO replace with a better error handler */
+    mx_handle_t handles[MAX_HANDLE_ARGS + 1];
+
+    mx_bootstrap_handle_t handle_info[MAX_HANDLE_ARGS + 1];
+
+    dbg_log("receiving message from handle %lx\n", bootstrap);
+    mx_status_t err = mx_tunnel_read(bootstrap,
+            arg_msg_buf, MAX_MSG_SIZE,
+            handles, MAX_HANDLE_ARGS,
+            &msg_size, &nr_handles);
+
+    if (err != MX_OK) {
         dbg_log("error: cannot read bootstrap message from handle %lx (error %d)\n",
-                bootstrap, status);
-        hang();
+                bootstrap, err);
+        return -1;
     }
 
-    unsigned char msg_buf[msg_size];
-    mx_handle_t handles[nr_handles];
-    mx_tunnel_read(bootstrap, msg_buf, msg_size, handles, nr_handles, &msg_size, &nr_handles);
+    mx_bootstrap_msg_t *msg = (mx_bootstrap_msg_t *)arg_msg_buf;
 
-    mx_bootstrap_msg_t *msg = (mx_bootstrap_msg_t *)msg_buf;
+    dbg_log("extracting handles\n");
+    extract_arg_handles(msg, handles, nr_handles, handle_info);
+    handle_info[nr_handles].handle = bootstrap;
+    handle_info[nr_handles].info = MX_B_HND(MX_B_TUNNEL_BTSTP, 0);
+    nr_handles++;
 
-    const char *argv[msg->args_num + 1];
-    const char *envp[msg->environ_num + 1];
-#ifdef LIBSYSTEM_STATIC
-    mx_bootstrap_handle_t start_handles[nr_handles + 1];
-    start_handles[nr_handles].handle = bootstrap;
-    start_handles[nr_handles].info = MX_B_HND(MX_B_TUNNEL_BTSTP, 0);
-#else
-    mx_bootstrap_handle_t start_handles[nr_handles];
-    mx_handle_close(bootstrap);
-#endif
+    mx_bootstrap_handle_init(handle_info, nr_handles);
+
+    const char **argv = NULL, **envp = NULL, **namep = NULL;
+
+    dbg_log("allocating buffers (%u, %u, %u)\n", msg->args_num, msg->environ_num, msg->names_num);
+
+    argv =  calloc(sizeof *argv,  msg->args_num    + 1);
+    envp =  calloc(sizeof *envp,  msg->environ_num + 1);
+    namep = calloc(sizeof *namep, msg->names_num   + 1);
 
-    argv[msg->args_num] = NULL;
-    envp[msg->environ_num] = NULL;
     environ = envp;
 
-    parse_args(msg, handles, argv, envp, nr_handles, start_handles);
-#ifdef LIBSYSTEM_STATIC
-    mx_bootstrap_handle_init(start_handles, nr_handles + 1);
-#else
-    mx_bootstrap_handle_init(start_handles, nr_handles);
-#endif
+    parse_args(msg, argv, envp, namep);
 
-    init_stdio(start_handles, nr_handles);
+    init_stdio(handle_info, nr_handles);
 
     dbg_log("calling main\n");
     int ret = main(msg->args_num, argv);