utils: split-off the message id parsing

* utils/rpctrace.c: Move all the code handling the message id files...
* utils/msgids.c: ... to a new file.
* utils/msgids.h: And add the relevand declarations.
* utils/Makefile (SRCS): Add the new file.

4 files changed, 298 insertions, 197 deletions

diff --git a/utils/Makefile b/utils/Makefile
index 1117be16..9ad2a40e 100644
--- a/utils/Makefile
+++ b/utils/Makefile
@@ -31,7 +31,7 @@ SRCS = shd.c ps.c settrans.c syncfs.c showtrans.c addauth.c rmauth.c \
 	parse.c frobauth.c frobauth-mod.c setauth.c pids.c nonsugid.c \
 	unsu.c ftpcp.c ftpdir.c storeread.c storecat.c msgport.c \
 	rpctrace.c mount.c gcore.c fakeauth.c fakeroot.sh remap.sh \
-	nullauth.c match-options.c
+	nullauth.c match-options.c msgids.c
 
 OBJS = $(filter-out %.sh,$(SRCS:.c=.o))
 HURDLIBS = ps ihash store fshelp ports ftpconn shouldbeinlibc
@@ -67,8 +67,10 @@ ps w ids settrans syncfs showtrans fsysopts storeinfo login vmstat portinfo \
 
 $(filter-out $(special-targets), $(targets)): %: %.o
 
-rpctrace: ../libports/libports.a ../libihash/libihash.a
-rpctrace-CPPFLAGS = -DDATADIR=\"${datadir}\"
+rpctrace: ../libports/libports.a
+rpctrace: msgids.o \
+	  ../libihash/libihash.a
+msgids-CPPFLAGS = -DDATADIR=\"${datadir}\"
 
 fakeauth: authServer.o auth_requestUser.o interruptServer.o \
 	  ../libports/libports.a ../libihash/libihash.a \
diff --git a/utils/msgids.c b/utils/msgids.c
new file mode 100644
index 00000000..4bc08ded
--- /dev/null
+++ b/utils/msgids.c
@@ -0,0 +1,252 @@
+/* Translate message ids to symbolic names.
+
+   Copyright (C) 1998-2015 Free Software Foundation, Inc.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd 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 2, or (at
+   your option) any later version.
+
+   The GNU Hurd 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 the GNU Hurd.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <argp.h>
+#include <argz.h>
+#include <dirent.h>
+#include <errno.h>
+#include <error.h>
+#include <fnmatch.h>
+#include <hurd/ihash.h>
+#include <mach.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "msgids.h"
+
+static void
+msgid_ihash_cleanup (void *element, void *arg)
+{
+  struct msgid_info *info = element;
+  free (info->name);
+  free (info->subsystem);
+  free (info);
+}
+
+static struct hurd_ihash msgid_ihash
+  = HURD_IHASH_INITIALIZER (HURD_IHASH_NO_LOCP);
+
+/* Parse a file of RPC names and message IDs as output by mig's -list
+   option: "subsystem base-id routine n request-id reply-id".  Put each
+   request-id value into `msgid_ihash' with the routine name as its value.  */
+static error_t
+parse_msgid_list (const char *filename)
+{
+  FILE *fp;
+  char *buffer = NULL;
+  size_t bufsize = 0;
+  unsigned int lineno = 0;
+  char *name, *subsystem;
+  unsigned int msgid;
+  error_t err;
+
+  fp = fopen (filename, "r");
+  if (fp == NULL)
+    return errno;
+
+  while (getline (&buffer, &bufsize, fp) > 0)
+    {
+      ++lineno;
+      if (buffer[0] == '#' || buffer[0] == '\0')
+	continue;
+      if (sscanf (buffer, "%ms %*u %ms %*u %u %*u\n",
+		  &subsystem, &name, &msgid) != 3)
+	error (0, 0, "%s:%u: invalid format in RPC list file",
+	       filename, lineno);
+      else
+	{
+	  struct msgid_info *info = malloc (sizeof *info);
+	  if (info == 0)
+	    error (1, errno, "malloc");
+	  info->name = name;
+	  info->subsystem = subsystem;
+	  err = hurd_ihash_add (&msgid_ihash, msgid, info);
+	  if (err)
+	    return err;
+	}
+    }
+
+  free (buffer);
+  fclose (fp);
+  return 0;
+}
+
+/* Look for a name describing MSGID.  We check the table directly, and
+   also check if this looks like the ID of a reply message whose request
+   ID is already in the table.  */
+const struct msgid_info *
+msgid_info (mach_msg_id_t msgid)
+{
+  const struct msgid_info *info = hurd_ihash_find (&msgid_ihash, msgid);
+  if (info == 0 && (msgid / 100) % 2 == 1)
+    {
+      /* This message ID is not in the table, and its number makes it
+	 what should be an RPC reply message ID.  So look up the message
+	 ID of the corresponding RPC request and synthesize a name from
+	 that.  Then stash that name in the table so the next time the
+	 lookup will match directly.  */
+      info = hurd_ihash_find (&msgid_ihash, msgid - 100);
+      if (info != 0)
+	{
+	  struct msgid_info *reply_info = malloc (sizeof *info);
+	  if (reply_info != 0)
+	    {
+	      reply_info->subsystem = strdup (info->subsystem);
+	      reply_info->name = 0;
+	      asprintf (&reply_info->name, "%s-reply", info->name);
+	      hurd_ihash_add (&msgid_ihash, msgid, reply_info);
+	      info = reply_info;
+	    }
+	  else
+	    info = 0;
+	}
+    }
+  return info;
+}
+
+static int
+msgids_file_p (const struct dirent *eps)
+{
+  return fnmatch ("*.msgids", eps->d_name, 0) != FNM_NOMATCH;
+}
+
+static void
+scan_msgids_dir (char **argz, size_t *argz_len, char *dir, bool append)
+{
+  struct dirent **eps;
+  int n;
+
+  n = scandir (dir, &eps, msgids_file_p, NULL);
+  if (n >= 0)
+    {
+      for (int cnt = 0; cnt < n; ++cnt)
+	{
+	  char *msgids_file;
+
+	  if (asprintf (&msgids_file, "%s/%s", dir, eps[cnt]->d_name) < 0)
+	    error (1, errno, "asprintf");
+
+	  if (append == TRUE)
+	    {
+	      if (argz_add (argz, argz_len, msgids_file) != 0)
+		error (1, errno, "argz_add");
+	    }
+	  else
+	    {
+	      if (argz_insert (argz, argz_len, *argz, msgids_file) != 0)
+		error (1, errno, "argz_insert");
+	    }
+	  free (msgids_file);
+	}
+    }
+
+  /* If the directory couldn't be scanned for whatever reason, just ignore
+     it. */
+}
+
+/* Argument parsing.  */
+
+static char *msgids_files_argz = NULL;
+static size_t msgids_files_argz_len = 0;
+static bool nostdinc = FALSE;
+
+#define STD_MSGIDS_DIR DATADIR "/msgids/"
+#define OPT_NOSTDINC -1
+
+static const struct argp_option options[] =
+{
+  {"nostdinc", OPT_NOSTDINC, 0, 0,
+   "Do not search inside the standard system directory, `" STD_MSGIDS_DIR
+   "', for `.msgids' files.", 0},
+  {"rpc-list", 'i', "FILE", 0,
+   "Read FILE for assocations of message ID numbers to names.", 0},
+  {0, 'I', "DIR", 0,
+   "Add the directory DIR to the list of directories to be searched for files "
+   "containing message ID numbers.", 0},
+  {0}
+};
+
+/* Parse our options...  */
+static error_t parse_opt (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case ARGP_KEY_INIT:
+      hurd_ihash_set_cleanup (&msgid_ihash, msgid_ihash_cleanup, 0);
+      break;
+
+    case OPT_NOSTDINC:
+      nostdinc = TRUE;
+      break;
+
+    case 'i':
+      if (argz_add (&msgids_files_argz, &msgids_files_argz_len,
+		    arg) != 0)
+	error (1, errno, "argz_add");
+      break;
+
+    case 'I':
+      scan_msgids_dir (&msgids_files_argz, &msgids_files_argz_len,
+		       arg, TRUE);
+      break;
+
+    case ARGP_KEY_NO_ARGS:
+      return 0;
+
+    case ARGP_KEY_ARG:
+      return EINVAL;
+
+    case ARGP_KEY_END:
+      /* Insert the files from STD_MSGIDS_DIR at the beginning of the
+	 list, so that their content can be overridden by subsequently
+	 parsed files.  */
+      if (nostdinc == FALSE)
+	scan_msgids_dir (&msgids_files_argz, &msgids_files_argz_len,
+			 STD_MSGIDS_DIR, FALSE);
+
+      if (msgids_files_argz != NULL)
+	{
+	  error_t err = 0;
+	  char *msgids_file = NULL;
+
+	  while (! err
+		 && (msgids_file = argz_next (msgids_files_argz,
+					      msgids_files_argz_len,
+					      msgids_file)))
+	    err = parse_msgid_list (msgids_file);
+
+	  free (msgids_files_argz);
+	  if (err)
+	    argp_failure (state, 1, err, "%s", msgids_file);
+	}
+      break;
+
+    default:
+      return ARGP_ERR_UNKNOWN;
+    }
+  return 0;
+}
+
+const struct argp msgid_argp = {
+  .options = options,
+  .parser = parse_opt,
+  .doc = "msgid doc",
+};
diff --git a/utils/msgids.h b/utils/msgids.h
new file mode 100644
index 00000000..6bd23720
--- /dev/null
+++ b/utils/msgids.h
@@ -0,0 +1,33 @@
+/* Translate message ids to symbolic names.
+
+   Copyright (C) 1998-2015 Free Software Foundation, Inc.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd 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 2, or (at
+   your option) any later version.
+
+   The GNU Hurd 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 the GNU Hurd.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef _HURD_MSGIDS_H_
+#define _HURD_MSGIDS_H_
+
+/* We map message ids to procedure and subsystem names.  */
+struct msgid_info
+{
+  char *name;
+  char *subsystem;
+};
+
+const struct msgid_info *msgid_info (mach_msg_id_t msgid);
+const struct argp msgid_argp;
+
+#endif	/* _HURD_MSGIDS_H_ */
diff --git a/utils/rpctrace.c b/utils/rpctrace.c
index 48daa078..d53b510f 100644
--- a/utils/rpctrace.c
+++ b/utils/rpctrace.c
@@ -26,9 +26,7 @@
 #include <mach/message.h>
 #include <assert.h>
 #include <fcntl.h>
-#include <fnmatch.h>
 #include <sys/stat.h>
-#include <dirent.h>
 #include <unistd.h>
 #include <argp.h>
 #include <error.h>
@@ -41,24 +39,15 @@
 #include <argz.h>
 #include <envz.h>
 
-const char *argp_program_version = STANDARD_HURD_VERSION (rpctrace);
+#include "msgids.h"
 
-#define STD_MSGIDS_DIR DATADIR "/msgids/"
+const char *argp_program_version = STANDARD_HURD_VERSION (rpctrace);
 
 static unsigned strsize = 80;
 
-#define OPT_NOSTDINC -1
 static const struct argp_option options[] =
 {
   {"output", 'o', "FILE", 0, "Send trace output to FILE instead of stderr."},
-  {"nostdinc", OPT_NOSTDINC, 0, 0, 
-   "Do not search inside the standard system directory, `" STD_MSGIDS_DIR
-   "', for `.msgids' files."},
-  {"rpc-list", 'i', "FILE", 0,
-   "Read FILE for assocations of message ID numbers to names."},
-  {0, 'I', "DIR", 0,
-   "Add the directory DIR to the list of directories to be searched for files "
-   "containing message ID numbers."},
   {0, 's', "SIZE", 0, "Specify the maximum string size to print (the default is 80)."},
   {0, 'E', "var[=value]", 0,
    "Set/change (var=value) or remove (var) an environment variable among the "
@@ -71,23 +60,6 @@ static const struct argp_option options[] =
 static const char args_doc[] = "COMMAND [ARG...]";
 static const char doc[] = "Trace Mach Remote Procedure Calls.";
 
-/* The msgid_ihash table maps msgh_id values to names.  */
-
-struct msgid_info
-{
-  char *name;
-  char *subsystem;
-};
-
-static void
-msgid_ihash_cleanup (void *element, void *arg)
-{
-  struct msgid_info *info = element;
-  free (info->name);
-  free (info->subsystem);
-  free (info);
-}
-
 /* This structure stores the information of the traced task. */
 struct task_info
 {
@@ -95,9 +67,6 @@ struct task_info
   boolean_t threads_wrapped;	/* All threads of the task has been wrapped? */
 };
 
-static struct hurd_ihash msgid_ihash
-  = HURD_IHASH_INITIALIZER (HURD_IHASH_NO_LOCP);
-
 static struct hurd_ihash task_ihash
   = HURD_IHASH_INITIALIZER (HURD_IHASH_NO_LOCP);
 
@@ -126,86 +95,6 @@ remove_task (task_t task)
   hurd_ihash_remove (&task_ihash, task);
 }
 
-/* Parse a file of RPC names and message IDs as output by mig's -list
-   option: "subsystem base-id routine n request-id reply-id".  Put each
-   request-id value into `msgid_ihash' with the routine name as its value.  */
-static void
-parse_msgid_list (const char *filename)
-{
-  FILE *fp;
-  char *buffer = NULL;
-  size_t bufsize = 0;
-  unsigned int lineno = 0;
-  char *name, *subsystem;
-  unsigned int msgid;
-  error_t err;
-
-  fp = fopen (filename, "r");
-  if (fp == 0)
-    {
-      error (2, errno, "%s", filename);
-      return;
-    }
-
-  while (getline (&buffer, &bufsize, fp) > 0)
-    {
-      ++lineno;
-      if (buffer[0] == '#' || buffer[0] == '\0')
-	continue;
-      if (sscanf (buffer, "%ms %*u %ms %*u %u %*u\n",
-		  &subsystem, &name, &msgid) != 3)
-	error (0, 0, "%s:%u: invalid format in RPC list file",
-	       filename, lineno);
-      else
-	{
-	  struct msgid_info *info = malloc (sizeof *info);
-	  if (info == 0)
-	    error (1, errno, "malloc");
-	  info->name = name;
-	  info->subsystem = subsystem;
-	  err = hurd_ihash_add (&msgid_ihash, msgid, info);
-	  if (err)
-	    error (1, err, "hurd_ihash_add");
-	}
-    }
-
-  free (buffer);
-  fclose (fp);
-}
-
-/* Look for a name describing MSGID.  We check the table directly, and
-   also check if this looks like the ID of a reply message whose request
-   ID is already in the table.  */
-static const struct msgid_info *
-msgid_info (mach_msg_id_t msgid)
-{
-  const struct msgid_info *info = hurd_ihash_find (&msgid_ihash, msgid);
-  if (info == 0 && (msgid / 100) % 2 == 1)
-    {
-      /* This message ID is not in the table, and its number makes it
-	 what should be an RPC reply message ID.  So look up the message
-	 ID of the corresponding RPC request and synthesize a name from
-	 that.  Then stash that name in the table so the next time the
-	 lookup will match directly.  */
-      info = hurd_ihash_find (&msgid_ihash, msgid - 100);
-      if (info != 0)
-	{
-	  struct msgid_info *reply_info = malloc (sizeof *info);
-	  if (reply_info != 0)
-	    {
-	      reply_info->subsystem = strdup (info->subsystem);
-	      reply_info->name = 0;
-	      asprintf (&reply_info->name, "%s-reply", info->name);
-	      hurd_ihash_add (&msgid_ihash, msgid, reply_info);
-	      info = reply_info;
-	    }
-	  else
-	    info = 0;
-	}
-    }
-  return info;
-}
-
 static const char *
 msgid_name (mach_msg_id_t msgid)
 {
@@ -1781,55 +1670,9 @@ traced_spawn (char **argv, char **envp)
   return pid;
 }
 
-
-static void
-scan_msgids_dir (char **argz, size_t *argz_len, char *dir, bool append)
-{
-  struct dirent **eps;
-  int n;
-	    
-  int
-    msgids_file_p (const struct dirent *eps)
-    {
-      if (fnmatch ("*.msgids", eps->d_name, 0) != FNM_NOMATCH)
-        return 1;
-      return 0;
-    }
-	    
-  n = scandir (dir, &eps, msgids_file_p, NULL);
-  if (n >= 0)
-    {
-      for (int cnt = 0; cnt < n; ++cnt)
-	{
-	  char *msgids_file;
-
-	  if (asprintf (&msgids_file, "%s/%s", dir, eps[cnt]->d_name) < 0)
-	    error (1, errno, "asprintf");
-
-	  if (append == TRUE)
-	    {
-	      if (argz_add (argz, argz_len, msgids_file) != 0)
-		error (1, errno, "argz_add");
-	    }
-	  else
-	    {
-	      if (argz_insert (argz, argz_len, *argz, msgids_file) != 0)
-		error (1, errno, "argz_insert");
-	    }
-	  free (msgids_file);
-	}
-    }
-
-  /* If the directory couldn't be scanned for whatever reason, just ignore
-     it. */
-}
-
 int
 main (int argc, char **argv, char **envp)
 {
-  char *msgids_files_argz = NULL;
-  size_t msgids_files_argz_len = 0;
-  bool nostdinc = FALSE;
   const char *outfile = 0;
   char **cmd_argv = 0;
   pthread_t thread;
@@ -1847,21 +1690,6 @@ main (int argc, char **argv, char **envp)
 	  outfile = arg;
 	  break;
 
-	case OPT_NOSTDINC:
-	  nostdinc = TRUE;
-	  break;
-
-	case 'i':
-	  if (argz_add (&msgids_files_argz, &msgids_files_argz_len, 
-			arg) != 0)
-	    error (1, errno, "argz_add");
-	  break;
-
-	case 'I':
-	  scan_msgids_dir (&msgids_files_argz, &msgids_files_argz_len,
-			  arg, TRUE);
-	  break;
-
 	case 's':
 	  strsize = atoi (arg);
 	  break;
@@ -1908,7 +1736,12 @@ main (int argc, char **argv, char **envp)
 	}
       return 0;
     }
-  const struct argp argp = { options, parse_opt, args_doc, doc };
+  const struct argp_child children[] =
+    {
+      { .argp=&msgid_argp, },
+      { 0 }
+    };
+  const struct argp argp = { options, parse_opt, args_doc, doc, &children };
 
   /* Parse our arguments.  */
   argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, 0);
@@ -1917,23 +1750,6 @@ main (int argc, char **argv, char **envp)
 			    &unknown_task);
   assert_perror (err);
 
-  /* Insert the files from STD_MSGIDS_DIR at the beginning of the list, so that
-     their content can be overridden by subsequently parsed files.  */
-  if (nostdinc == FALSE)
-    scan_msgids_dir (&msgids_files_argz, &msgids_files_argz_len,
-		    STD_MSGIDS_DIR, FALSE);
-
-  if (msgids_files_argz != NULL)
-    {
-      char *msgids_file = NULL;
-
-      while ((msgids_file = argz_next (msgids_files_argz,
-				       msgids_files_argz_len, msgids_file)))
-	parse_msgid_list (msgids_file);
-
-      free (msgids_files_argz);
-    }
-
   if (outfile)
     {
       ostream = fopen (outfile, "w");
@@ -1951,8 +1767,6 @@ main (int argc, char **argv, char **envp)
 			   sizeof (*notify_pi), &notify_pi);
   assert_perror (err);
 
-  hurd_ihash_set_cleanup (&msgid_ihash, msgid_ihash_cleanup, 0);
-
   /* Spawn a single thread that will receive intercepted messages, print
      them, and interpose on the ports they carry.  The access to the
      `traced_info' and ihash data structures is all single-threaded,