mds-server: parse command line arguments

Signed-off-by: Mattias Andrée <maandree@operamail.com>

4 files changed, 168 insertions, 11 deletions

diff --git a/Makefile b/Makefile
index a9080e9..eafecdb 100644
--- a/Makefile
+++ b/Makefile
@@ -62,15 +62,14 @@ C_FLAGS = $(OPTIMISE) $(WARN) -std=$(STD) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS)  \
 # Build rules.
 
 .PHONY: all
-all: bin/mds
+all: bin/mds bin/mds-server
 
 
-bin/mds: obj/mds.o
+bin/%: obj/%.o
 	mkdir -p bin
 	gcc $(C_FLAGS) -o $@ $^
 
-
-obj/%.o: src/%.c src/*.h
+obj/%.o: src/%.c src/%.h src/config.h
 	mkdir -p obj
 	gcc $(C_FLAGS) -c -o $@ $<
 
diff --git a/src/mds-server.c b/src/mds-server.c
new file mode 100644
index 0000000..e532c72
--- /dev/null
+++ b/src/mds-server.c
@@ -0,0 +1,137 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "mds-server.h"
+#include "config.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <limits.h>
+
+
+/**
+ * Number of elements in `argv`
+ */
+static int argc;
+
+/**
+ * Command line arguments
+ */
+static char** argv;
+
+
+/**
+ * Entry point of the server
+ * 
+ * @param   argc_  Number of elements in `argv_`
+ * @param   argv_  Command line arguments
+ * @return         Non-zero on error
+ */
+int main(int argc_, char** argv_)
+{
+  char* unparsed_args[ARGC_LIMIT + LIBEXEC_ARGC_EXTRA_LIMIT + 1];
+  int i;
+  int is_respawn = -1;
+  int socket_fd = -1;
+  int unparsed_args_ptr = 0;
+  
+  
+  argc = argc_;
+  argv = argv_;
+  
+  
+  /* Sanity check the number of command line arguments. */
+  if (argc > ARGC_LIMIT + LIBEXEC_ARGC_EXTRA_LIMIT)
+    {
+      fprintf(stderr,
+	      "%s: that number of arguments is ridiculous, I will not allow it.\n",
+	      *argv);
+      return 1;
+    }
+  
+  
+  /* Parse command line arguments. */
+  for (i = 1; i < argc; i++)
+    {
+      char* arg = argv[i];
+      if (!strcmp(arg, "--initial-spawn")) /* Initial spawn? */
+	if (is_respawn == 1)
+	  {
+	    fprintf(stderr,
+		    "%s: conflicting arguments %s and %s cannot be combined.\n",
+		    *argv, "--initial-spawn", "--respawn");
+	    return 1;
+	  }
+	else
+	  is_respawn = 0;
+      else if (!strcmp(arg, "--respawn")) /* Respawning after crash? */
+	if (is_respawn == 0)
+	  {
+	    fprintf(stderr,
+		    "%s: conflicting arguments %s and %s cannot be combined.\n",
+		    *argv, "--initial-spawn", "--respawn");
+	    return 1;
+	  }
+	else
+	  is_respawn = 1;
+      else if (strstr(arg, "--socket-fd=") == arg) /* Socket file descriptor. */
+	{
+	  long int r;
+	  char* endptr;
+	  if (socket_fd != -1)
+	    {
+	      fprintf(stderr, "%s: duplicate declaration of %s.\n", *argv, "--socket-fd");
+	      return -1;
+	    }
+	  arg += strlen("--socket-fd=");
+	  r = strtol(arg, &endptr, 10);
+	  if ((*argv == '\0') || isspace(*argv) ||
+	      (endptr - arg != (ssize_t)strlen(arg))
+	      || (r < 0) || (r > INT_MAX))
+	    {
+	      fprintf(stderr, "%s: invalid value for %s: %s.\n", *argv, "--socket-fd", arg);
+	      return 1;
+	    }
+	  socket_fd = (int)r;
+	}
+      else
+	/* Not recognised, it is probably for another server. */
+	unparsed_args[unparsed_args_ptr++] = arg;
+    }
+  unparsed_args[unparsed_args_ptr] = NULL;
+  
+  
+  /* Check that manditory arguments have been specified. */
+  if (is_respawn < 0)
+    {
+      fprintf(stderr,
+	      "%s: missing state argument, require either %s or %s.\n",
+	      *argv, "--initial-spawn", "--respawn");
+      return 1;
+    }
+  if (socket_fd < 0)
+    {
+      fprintf(stderr, "%s: missing socket file descriptor argument.\n", *argv);
+      return 1;
+    }
+  
+  
+  return 0;
+}
+
diff --git a/src/mds-server.h b/src/mds-server.h
new file mode 100644
index 0000000..4b558dd
--- /dev/null
+++ b/src/mds-server.h
@@ -0,0 +1,22 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MDS_MDS_SERVER_H
+#define MDS_MDS_SERVER_H
+
+#endif
+
diff --git a/src/mds.c b/src/mds.c
index d1ab07f..a263173 100644
--- a/src/mds.c
+++ b/src/mds.c
@@ -246,7 +246,7 @@ int spawn_and_respawn_server(int fd)
   struct timespec time_end;
   char* child_args[ARGC_LIMIT + LIBEXEC_ARGC_EXTRA_LIMIT + 1];
   char pathname[PATH_MAX];
-  char fdstr[64];
+  char fdstr[12 /* strlen("--socket-fd=") */ + 64];
   int i;
   pid_t pid;
   int status;
@@ -260,13 +260,12 @@ int spawn_and_respawn_server(int fd)
     child_args[i] = argv[i];
   
   child_args[argc + 0] = strdup("--initial-spawn");
-  child_args[argc + 1] = strdup("--socket-fd");
-  snprintf(fdstr, sizeof(fdstr) / sizeof(char), "%i", fd);
-  child_args[argc + 2] = fdstr;
-  child_args[argc + 3] = NULL;
+  snprintf(fdstr, sizeof(fdstr) / sizeof(char), "--socket-fd=%i", fd);
+  child_args[argc + 1] = fdstr;
+  child_args[argc + 2] = NULL;
   
-#if (LIBEXEC_ARGC_EXTRA_LIMIT < 3)
-# error LIBEXEC_ARGC_EXTRA_LIMIT is too small, need at least 3.
+#if (LIBEXEC_ARGC_EXTRA_LIMIT < 2)
+# error LIBEXEC_ARGC_EXTRA_LIMIT is too small, need at least 2.
 #endif
   
   for (;;)