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-rw-r--r--src/libmdsserver/util.c82
-rw-r--r--src/libmdsserver/util.h43
-rw-r--r--src/mds-server.c47
-rw-r--r--src/mds-server.h8
4 files changed, 130 insertions, 50 deletions
diff --git a/src/libmdsserver/util.c b/src/libmdsserver/util.c
new file mode 100644
index 0000000..c4606e8
--- /dev/null
+++ b/src/libmdsserver/util.c
@@ -0,0 +1,82 @@
+/**
+ * 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 "util.h"
+#include "config.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <limits.h>
+#include <string.h>
+
+
+/**
+ * Read an environment variable, but handle it as undefined if empty
+ *
+ * @param var The environment variable's name
+ * @return The environment variable's value, `NULL` if empty or not defined
+ */
+char* getenv_nonempty(const char* var)
+{
+ char* rc = getenv(var);
+ if ((rc == NULL) || (*rc == '\0'))
+ return NULL;
+ return rc;
+}
+
+
+/**
+ * Re-exec the server.
+ * This function only returns on failure.
+ *
+ * @param argc The number of elements in `argv`
+ * @param argv The command line arguments
+ * @param reexeced Whether the server has previously been re-exec:ed
+ */
+void reexec_server(int argc, char** argv, int reexeced)
+{
+ char readlink_buf[PATH_MAX];
+ ssize_t readlink_ptr;
+ char** reexec_args;
+ char** reexec_args_;
+ int i;
+
+ /* Re-exec the server. */
+ readlink_ptr = readlink(SELF_EXE, readlink_buf, (sizeof(readlink_buf) / sizeof(char)) - 1);
+ if (readlink_ptr < 0)
+ return;
+ /* ‘readlink() does not append a null byte to buf.’ */
+ readlink_buf[readlink_ptr] = '\0';
+ reexec_args = alloca(((size_t)argc + 2) * sizeof(char*));
+ reexec_args_ = reexec_args;
+ if (reexeced == 0)
+ {
+ *reexec_args_++ = *argv;
+ *reexec_args_ = strdup("--re-exec");
+ if (*reexec_args_)
+ return;
+ for (i = 1; i < argc; i++)
+ reexec_args_[i] = argv[i];
+ }
+ else /* Don't let the --re-exec:s accumulate. */
+ *reexec_args_ = *argv;
+ for (i = 1; i < argc; i++)
+ reexec_args_[i] = argv[i];
+ reexec_args_[argc] = NULL;
+ execv(readlink_buf, reexec_args);
+}
+
diff --git a/src/libmdsserver/util.h b/src/libmdsserver/util.h
new file mode 100644
index 0000000..f1276f7
--- /dev/null
+++ b/src/libmdsserver/util.h
@@ -0,0 +1,43 @@
+/**
+ * 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_LIBMDSSERVER_UTIL_H
+#define MDS_LIBMDSSERVER_UTIL_H
+
+
+/**
+ * Read an environment variable, but handle it as undefined if empty
+ *
+ * @param var The environment variable's name
+ * @return The environment variable's value, `NULL` if empty or not defined
+ */
+char* getenv_nonempty(const char* var);
+
+
+/**
+ * Re-exec the server.
+ * This function only returns on failure.
+ *
+ * @param argc The number of elements in `argv`
+ * @param argv The command line arguments
+ * @param reexeced Whether the server has previously been re-exec:ed
+ */
+void reexec_server(int argc, char** argv, int reexeced);
+
+
+#endif
+
diff --git a/src/mds-server.c b/src/mds-server.c
index 04f2124..8c9a863 100644
--- a/src/mds-server.c
+++ b/src/mds-server.c
@@ -23,6 +23,7 @@
#include <libmdsserver/fd-table.h>
#include <libmdsserver/mds-message.h>
#include <libmdsserver/macros.h>
+#include <libmdsserver/util.h>
#include <alloca.h>
#include <signal.h>
@@ -398,10 +399,6 @@ int main(int argc_, char** argv_)
pid_t pid = getpid();
int reexec_fd;
char shm_path[NAME_MAX + 1];
- char readlink_buf[PATH_MAX];
- ssize_t readlink_ptr;
- char** reexec_args;
- char** reexec_args_;
/* Release resources. */
pthread_mutex_destroy(&slave_mutex);
@@ -423,34 +420,15 @@ int main(int argc_, char** argv_)
if (marshal_server(reexec_fd) < 0)
goto reexec_fail;
close(reexec_fd);
+ reexec_fd = -1;
/* Re-exec the server. */
- readlink_ptr = readlink(SELF_EXE, readlink_buf, (sizeof(readlink_buf) / sizeof(char)) - 1);
- if (readlink_ptr < 0)
- goto reexec_fail;
- /* ‘readlink() does not append a null byte to buf.’ */
- readlink_buf[readlink_ptr] = '\0';
- reexec_args = alloca(((size_t)argc + 2) * sizeof(char*));
- reexec_args_ = reexec_args;
- if (reexec == 0)
- {
- *reexec_args_++ = *argv;
- *reexec_args_ = strdup("--re-exec");
- if (*reexec_args_)
- goto reexec_fail;
- for (i = 1; i < argc; i++)
- reexec_args_[i] = argv[i];
- }
- else /* Don't let the --re-exec:s accumulate. */
- *reexec_args_ = *argv;
- for (i = 1; i < argc; i++)
- reexec_args_[i] = argv[i];
- reexec_args_[argc] = NULL;
- execv(readlink_buf, reexec_args);
+ reexec_server(argc, argv, reexec);
reexec_fail:
perror(*argv);
- close(reexec_fd);
+ if (reexec_fd >= 0)
+ close(reexec_fd);
shm_unlink(shm_path);
/* Returning non-zero is important, otherwise the server cannot
be respawn if the re-exec fails. */
@@ -615,21 +593,6 @@ void* slave_loop(void* data)
/**
- * Read an environment variable, but handle it as undefined if empty
- *
- * @param var The environment variable's name
- * @return The environment variable's value, `NULL` if empty or not defined
- */
-char* getenv_nonempty(const char* var)
-{
- char* rc = getenv(var);
- if ((rc == NULL) || (*rc == '\0'))
- return NULL;
- return rc;
-}
-
-
-/**
* Exec into the mdsinitrc script
*
* @param args The arguments to the child process
diff --git a/src/mds-server.h b/src/mds-server.h
index 67e97f6..609d7cf 100644
--- a/src/mds-server.h
+++ b/src/mds-server.h
@@ -67,14 +67,6 @@ typedef struct client
void* slave_loop(void* data);
/**
- * Read an environment variable, but handle it as undefined if empty
- *
- * @param var The environment variable's name
- * @return The environment variable's value, `NULL` if empty or not defined
- */
-char* getenv_nonempty(const char* var);
-
-/**
* Exec into the mdsinitrc script
*
* @param args The arguments to the child process