run-command: factor out child_process_clear()

Avoid duplication by moving the code to release allocated memory for
arguments and environment to its own function, child_process_clear().
Export it to provide a counterpart to child_process_init().

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/technical/api-run-command.txt b/Documentation/technical/api-run-command.txt
index a9fdb45b93e514962716401cb22d9d079b107e40..8bf3e37f5375584e5c9f4543523a40377e08686f 100644 (file)
--- a/Documentation/technical/api-run-command.txt
+++ b/Documentation/technical/api-run-command.txt
@@ -46,6 +46,13 @@ Functions
        The argument dir corresponds the member .dir. The argument env
        corresponds to the member .env.
 
+`child_process_clear`::
+
+       Release the memory associated with the struct child_process.
+       Most users of the run-command API don't need to call this
+       function explicitly because `start_command` invokes it on
+       failure and `finish_command` calls it automatically already.
+
 The functions above do the following:
 
 . If a system call failed, errno is set and -1 is returned. A diagnostic

diff --git a/run-command.c b/run-command.c
index aad03ab705f301268980079282fcf370b9275c5a..fc391fb9cdd6977e8e40d00d2c6142fb824f99d1 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -11,6 +11,12 @@ void child_process_init(struct child_process *child)
        argv_array_init(&child->env_array);
 }
 
+void child_process_clear(struct child_process *child)
+{
+       argv_array_clear(&child->args);
+       argv_array_clear(&child->env_array);
+}
+
 struct child_to_clean {
        pid_t pid;
        struct child_to_clean *next;
@@ -336,8 +342,7 @@ int start_command(struct child_process *cmd)
 fail_pipe:
                        error("cannot create %s pipe for %s: %s",
                                str, cmd->argv[0], strerror(failed_errno));
-                       argv_array_clear(&cmd->args);
-                       argv_array_clear(&cmd->env_array);
+                       child_process_clear(cmd);
                        errno = failed_errno;
                        return -1;
                }
@@ -523,8 +528,7 @@ fail_pipe:
                        close_pair(fderr);
                else if (cmd->err)
                        close(cmd->err);
-               argv_array_clear(&cmd->args);
-               argv_array_clear(&cmd->env_array);
+               child_process_clear(cmd);
                errno = failed_errno;
                return -1;
        }
@@ -550,8 +554,7 @@ fail_pipe:
 int finish_command(struct child_process *cmd)
 {
        int ret = wait_or_whine(cmd->pid, cmd->argv[0]);
-       argv_array_clear(&cmd->args);
-       argv_array_clear(&cmd->env_array);
+       child_process_clear(cmd);
        return ret;
 }
 

diff --git a/run-command.h b/run-command.h
index 263b9662adeba011adcd018f77b7ccbbcd53e94a..c850a57ea6bae33a164af135df2f1edfb0118f4a 100644 (file)
--- a/run-command.h
+++ b/run-command.h
@@ -47,6 +47,7 @@ struct child_process {
 
 #define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
 void child_process_init(struct child_process *);
+void child_process_clear(struct child_process *);
 
 int start_command(struct child_process *);
 int finish_command(struct child_process *);