run-command: add env_array, an optional argv_array for env

Similar to args, add a struct argv_array member to struct child_process
that simplifies specifying the environment for children.  It is freed
automatically by finish_command() or if start_command() encounters an
error.

Suggested-by: Jeff King <peff@peff.net>
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 842b8389eb867b6db654cf7fe29e8f10b92b259e..3f12fcdd4c788d73c204751404670d299c7f95d2 100644 (file)
--- a/Documentation/technical/api-run-command.txt
+++ b/Documentation/technical/api-run-command.txt
@@ -169,6 +169,11 @@ string pointers (NULL terminated) in .env:
 . If the string does not contain '=', it names an environment
   variable that will be removed from the child process's environment.
 
+If the .env member is NULL, `start_command` will point it at the
+.env_array `argv_array` (so you may use one or the other, but not both).
+The memory in .env_array will be cleaned up automatically during
+`finish_command` (or during `start_command` when it is unsuccessful).
+
 To specify a new initial working directory for the sub-process,
 specify it in the .dir member.
 

diff --git a/run-command.c b/run-command.c
index 761f0fde40c91a3cc910c092c5aa9ad56f2f0042..46be513c480abf200148f7dcfc08c1c021410f7c 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -12,6 +12,7 @@ void child_process_init(struct child_process *child)
 {
        memset(child, 0, sizeof(*child));
        argv_array_init(&child->args);
+       argv_array_init(&child->env_array);
 }
 
 struct child_to_clean {
@@ -287,6 +288,8 @@ int start_command(struct child_process *cmd)
 
        if (!cmd->argv)
                cmd->argv = cmd->args.argv;
+       if (!cmd->env)
+               cmd->env = cmd->env_array.argv;
 
        /*
         * In case of errors we must keep the promise to close FDs
@@ -338,6 +341,7 @@ int start_command(struct child_process *cmd)
                        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);
                        errno = failed_errno;
                        return -1;
                }
@@ -524,6 +528,7 @@ int start_command(struct child_process *cmd)
                else if (cmd->err)
                        close(cmd->err);
                argv_array_clear(&cmd->args);
+               argv_array_clear(&cmd->env_array);
                errno = failed_errno;
                return -1;
        }
@@ -550,6 +555,7 @@ 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);
        return ret;
 }
 

diff --git a/run-command.h b/run-command.h
index 1b135d1c960aa58e2fa4ad44ecc195835daac69a..2137315ee46f672d945e0d3e011a8cbfbd5582a7 100644 (file)
--- a/run-command.h
+++ b/run-command.h
@@ -10,6 +10,7 @@
 struct child_process {
        const char **argv;
        struct argv_array args;
+       struct argv_array env_array;
        pid_t pid;
        /*
         * Using .in, .out, .err:
@@ -44,7 +45,7 @@ struct child_process {
        unsigned clean_on_exit:1;
 };
 
-#define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT }
+#define CHILD_PROCESS_INIT { NULL, ARGV_ARRAY_INIT, ARGV_ARRAY_INIT }
 void child_process_init(struct child_process *);
 
 int start_command(struct child_process *);