Changed wait_process() into a simpler, yet more versatile function,

[rsync/rsync.git] / main.c

diff --git a/main.c b/main.c
index da9946b..a9418f7 100644 (file)
--- a/main.c
+++ b/main.c
@@ -45,6 +45,7 @@ extern int copy_links;
 extern int keep_dirlinks;
 extern int preserve_hard_links;
 extern int protocol_version;
+extern int always_checksum;
 extern int recurse;
 extern int relative_paths;
 extern int rsync_port;
@@ -60,8 +61,10 @@ extern char *filesfrom_host;
 extern char *rsync_path;
 extern char *shell_cmd;
 extern char *batch_name;
+extern char curr_dir[MAXPATHLEN];
 
 int local_server = 0;
+int pre_checksum = 0;
 struct file_list *the_file_list;
 
 /* There's probably never more than at most 2 outstanding child processes,
@@ -78,33 +81,39 @@ static int64 total_read, total_written;
 
 static void show_malloc_stats(void);
 
-/****************************************************************************
-wait for a process to exit, calling io_flush while waiting
-****************************************************************************/
-static void wait_process(pid_t pid, int *code_ptr)
+/* Works like waitpid(), but if we already harvested the child pid in our
+ * sigchld_handler(), we succeed instead of returning an error. */
+pid_t wait_process(pid_t pid, int *status_ptr, int flags)
 {
-       pid_t waited_pid;
-       int cnt, status;
-
-       while ((waited_pid = waitpid(pid, &status, WNOHANG)) == 0) {
-               msleep(20);
-               io_flush(FULL_FLUSH);
-       }
+       pid_t waited_pid = waitpid(pid, status_ptr, flags);
 
        if (waited_pid == -1 && errno == ECHILD) {
-               /* status of requested child no longer available.
-                * check to see if it was processed by the sigchld_handler.
-                */
+               /* Status of requested child no longer available:  check to
+                * see if it was processed by sigchld_handler(). */
+               int cnt;
                for (cnt = 0;  cnt < MAXCHILDPROCS; cnt++) {
                        if (pid == pid_stat_table[cnt].pid) {
-                               waited_pid = pid;
-                               status = pid_stat_table[cnt].status;
+                               *status_ptr = pid_stat_table[cnt].status;
                                pid_stat_table[cnt].pid = 0;
-                               break;
+                               return pid;
                        }
                }
        }
 
+       return waited_pid;
+}
+
+/* Wait for a process to exit, calling io_flush while waiting. */
+static void wait_process_with_flush(pid_t pid, int *code_ptr)
+{
+       pid_t waited_pid;
+       int status;
+
+       while ((waited_pid = wait_process(pid, &status, WNOHANG)) == 0) {
+               msleep(20);
+               io_flush(FULL_FLUSH);
+       }
+
        /* TODO: If the child exited on a signal, then log an
         * appropriate error message.  Perhaps we should also accept a
         * message describing the purpose of the child.  Also indicate
@@ -112,9 +121,12 @@ static void wait_process(pid_t pid, int *code_ptr)
        if (waited_pid < 0)
                *code_ptr = RERR_WAITCHILD;
        else if (!WIFEXITED(status)) {
+#ifdef WCOREDUMP
                if (WCOREDUMP(status))
                        *code_ptr = RERR_CRASHED;
-               else if (WIFSIGNALED(status))
+               else
+#endif
+               if (WIFSIGNALED(status))
                        *code_ptr = RERR_TERMINATED;
                else
                        *code_ptr = RERR_WAITCHILD;
@@ -612,7 +624,7 @@ static int do_recv(int f_in,int f_out,struct file_list *flist,char *local_name)
 
        set_msg_fd_in(-1);
        kill(pid, SIGUSR2);
-       wait_process(pid, &status);
+       wait_process_with_flush(pid, &status);
        return status;
 }
 
@@ -623,6 +635,7 @@ static void do_server_recv(int f_in, int f_out, int argc,char *argv[])
        struct file_list *flist;
        char *local_name = NULL;
        char *dir = NULL;
+       char olddir[sizeof curr_dir];
        int save_verbose = verbose;
 
        if (filesfrom_fd >= 0) {
@@ -667,6 +680,10 @@ static void do_server_recv(int f_in, int f_out, int argc,char *argv[])
                filesfrom_fd = -1;
        }
 
+       strlcpy(olddir, curr_dir, sizeof olddir);
+       if (always_checksum && argc > 0)
+               pre_checksum = push_dir(argv[0]);
+
        flist = recv_file_list(f_in);
        verbose = save_verbose;
        if (!flist) {
@@ -675,6 +692,9 @@ static void do_server_recv(int f_in, int f_out, int argc,char *argv[])
        }
        the_file_list = flist;
 
+       if (pre_checksum)
+               pop_dir(olddir);
+
        if (argc > 0)
                local_name = get_local_name(flist,argv[0]);
 
@@ -723,6 +743,7 @@ int client_run(int f_in, int f_out, pid_t pid, int argc, char *argv[])
 {
        struct file_list *flist = NULL;
        int status = 0, status2 = 0;
+       char olddir[sizeof curr_dir];
        char *local_name = NULL;
 
        cleanup_child_pid = pid;
@@ -774,7 +795,7 @@ int client_run(int f_in, int f_out, pid_t pid, int argc, char *argv[])
                        if (verbose > 3)
                                rprintf(FINFO,"client_run waiting on %d\n", (int) pid);
                        io_flush(FULL_FLUSH);
-                       wait_process(pid, &status);
+                       wait_process_with_flush(pid, &status);
                }
                output_summary();
                io_flush(FULL_FLUSH);
@@ -794,11 +815,18 @@ int client_run(int f_in, int f_out, pid_t pid, int argc, char *argv[])
                filesfrom_fd = -1;
        }
 
+       strlcpy(olddir, curr_dir, sizeof olddir);
+       if (always_checksum)
+               pre_checksum = push_dir(argv[0]);
+
        if (write_batch && !am_server)
                start_write_batch(f_in);
        flist = recv_file_list(f_in);
        the_file_list = flist;
 
+       if (pre_checksum)
+               pop_dir(olddir);
+
        if (flist && flist->count > 0) {
                local_name = get_local_name(flist, argv[0]);
 
@@ -812,7 +840,7 @@ int client_run(int f_in, int f_out, pid_t pid, int argc, char *argv[])
                if (verbose > 3)
                        rprintf(FINFO,"client_run2 waiting on %d\n", (int) pid);
                io_flush(FULL_FLUSH);
-               wait_process(pid, &status);
+               wait_process_with_flush(pid, &status);
        }
 
        return MAX(status, status2);
@@ -1001,8 +1029,7 @@ static RETSIGTYPE sigchld_handler(UNUSED(int val))
         * get him to explain why he put it in, so rather than taking it
         * out we're instead saving the child exit statuses for later use.
         * The waitpid() loop presumably eliminates all possibility of leaving
-        * zombie children, maybe that's why he did it.
-        */
+        * zombie children, maybe that's why he did it. */
        while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
                /* save the child's exit status */
                for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) {
@@ -1014,6 +1041,7 @@ static RETSIGTYPE sigchld_handler(UNUSED(int val))
                }
        }
 #endif
+       signal(SIGCHLD, sigchld_handler);
 }