Merge branch 'rs/run-command-env-array'

Add managed "env" array to child_process to clarify the lifetime
rules.

* rs/run-command-env-array:
  use env_array member of struct child_process
  run-command: add env_array, an optional argv_array for env

8 files changed, 38 insertions, 39 deletions

diff --git a/Documentation/technical/api-run-command.txt b/Documentation/technical/api-run-command.txt
index 842b8389eb..3f12fcdd4c 100644
--- 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/builtin/receive-pack.c b/builtin/receive-pack.c
index 916315ff5c..fc0393779c 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -453,7 +453,6 @@ leave:
 static void prepare_push_cert_sha1(struct child_process *proc)
 {
 	static int already_done;
-	struct argv_array env = ARGV_ARRAY_INIT;
 
 	if (!push_cert.len)
 		return;
@@ -487,20 +486,26 @@ static void prepare_push_cert_sha1(struct child_process *proc)
 		nonce_status = check_nonce(push_cert.buf, bogs);
 	}
 	if (!is_null_sha1(push_cert_sha1)) {
-		argv_array_pushf(&env, "GIT_PUSH_CERT=%s", sha1_to_hex(push_cert_sha1));
-		argv_array_pushf(&env, "GIT_PUSH_CERT_SIGNER=%s",
+		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT=%s",
+				 sha1_to_hex(push_cert_sha1));
+		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_SIGNER=%s",
 				 sigcheck.signer ? sigcheck.signer : "");
-		argv_array_pushf(&env, "GIT_PUSH_CERT_KEY=%s",
+		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_KEY=%s",
 				 sigcheck.key ? sigcheck.key : "");
-		argv_array_pushf(&env, "GIT_PUSH_CERT_STATUS=%c", sigcheck.result);
+		argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_STATUS=%c",
+				 sigcheck.result);
 		if (push_cert_nonce) {
-			argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE=%s", push_cert_nonce);
-			argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE_STATUS=%s", nonce_status);
+			argv_array_pushf(&proc->env_array,
+					 "GIT_PUSH_CERT_NONCE=%s",
+					 push_cert_nonce);
+			argv_array_pushf(&proc->env_array,
+					 "GIT_PUSH_CERT_NONCE_STATUS=%s",
+					 nonce_status);
 			if (nonce_status == NONCE_SLOP)
-				argv_array_pushf(&env, "GIT_PUSH_CERT_NONCE_SLOP=%ld",
+				argv_array_pushf(&proc->env_array,
+						 "GIT_PUSH_CERT_NONCE_SLOP=%ld",
 						 nonce_stamp_slop);
 		}
-		proc->env = env.argv;
 	}
 }
 
diff --git a/http-backend.c b/http-backend.c
index 9977c5d499..b6c0484fb2 100644
--- a/http-backend.c
+++ b/http-backend.c
@@ -314,7 +314,6 @@ static void run_service(const char **argv)
 	const char *encoding = getenv("HTTP_CONTENT_ENCODING");
 	const char *user = getenv("REMOTE_USER");
 	const char *host = getenv("REMOTE_ADDR");
-	struct argv_array env = ARGV_ARRAY_INIT;
 	int gzipped_request = 0;
 	struct child_process cld = CHILD_PROCESS_INIT;
 
@@ -329,13 +328,12 @@ static void run_service(const char **argv)
 		host = "(none)";
 
 	if (!getenv("GIT_COMMITTER_NAME"))
-		argv_array_pushf(&env, "GIT_COMMITTER_NAME=%s", user);
+		argv_array_pushf(&cld.env_array, "GIT_COMMITTER_NAME=%s", user);
 	if (!getenv("GIT_COMMITTER_EMAIL"))
-		argv_array_pushf(&env, "GIT_COMMITTER_EMAIL=%s@http.%s",
-				 user, host);
+		argv_array_pushf(&cld.env_array,
+				 "GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
 
 	cld.argv = argv;
-	cld.env = env.argv;
 	if (gzipped_request)
 		cld.in = -1;
 	cld.git_cmd = 1;
@@ -350,7 +348,6 @@ static void run_service(const char **argv)
 
 	if (finish_command(&cld))
 		exit(1);
-	argv_array_clear(&env);
 }
 
 static int show_text_ref(const char *name, const unsigned char *sha1,
diff --git a/pager.c b/pager.c
index b2b805af98..f6e8c33192 100644
--- a/pager.c
+++ b/pager.c
@@ -74,17 +74,10 @@ void setup_pager(void)
 	pager_process.use_shell = 1;
 	pager_process.argv = pager_argv;
 	pager_process.in = -1;
-	if (!getenv("LESS") || !getenv("LV")) {
-		static const char *env[3];
-		int i = 0;
-
-		if (!getenv("LESS"))
-			env[i++] = "LESS=FRX";
-		if (!getenv("LV"))
-			env[i++] = "LV=-c";
-		env[i] = NULL;
-		pager_process.env = env;
-	}
+	if (!getenv("LESS"))
+		argv_array_push(&pager_process.env_array, "LESS=FRX");
+	if (!getenv("LV"))
+		argv_array_push(&pager_process.env_array, "LV=-c");
 	if (start_command(&pager_process))
 		return;
 
diff --git a/run-command.c b/run-command.c
index 761f0fde40..46be513c48 100644
--- 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 @@ 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);
 			errno = failed_errno;
 			return -1;
 		}
@@ -524,6 +528,7 @@ fail_pipe:
 		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 1b135d1c96..2137315ee4 100644
--- 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 *);
diff --git a/transport-helper.c b/transport-helper.c
index 9b2962041b..6cd9dd1f9f 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -108,12 +108,6 @@ static struct child_process *get_helper(struct transport *transport)
 	int refspec_alloc = 0;
 	int duped;
 	int code;
-	char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
-	const char *helper_env[] = {
-		git_dir_buf,
-		NULL
-	};
-
 
 	if (data->helper)
 		return data->helper;
@@ -129,8 +123,8 @@ static struct child_process *get_helper(struct transport *transport)
 	helper->git_cmd = 0;
 	helper->silent_exec_failure = 1;
 
-	snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
-	helper->env = helper_env;
+	argv_array_pushf(&helper->env_array, "%s=%s", GIT_DIR_ENVIRONMENT,
+			 get_git_dir());
 
 	code = start_command(helper);
 	if (code < 0 && errno == ENOENT)
diff --git a/wt-status.c b/wt-status.c
index f367066f92..cdbc8d798a 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -726,14 +726,14 @@ static void wt_status_print_changed(struct wt_status *s)
 static void wt_status_print_submodule_summary(struct wt_status *s, int uncommitted)
 {
 	struct child_process sm_summary = CHILD_PROCESS_INIT;
-	struct argv_array env = ARGV_ARRAY_INIT;
 	struct argv_array argv = ARGV_ARRAY_INIT;
 	struct strbuf cmd_stdout = STRBUF_INIT;
 	struct strbuf summary = STRBUF_INIT;
 	char *summary_content;
 	size_t len;
 
-	argv_array_pushf(&env, "GIT_INDEX_FILE=%s", s->index_file);
+	argv_array_pushf(&sm_summary.env_array, "GIT_INDEX_FILE=%s",
+			 s->index_file);
 
 	argv_array_push(&argv, "submodule");
 	argv_array_push(&argv, "summary");
@@ -745,14 +745,12 @@ static void wt_status_print_submodule_summary(struct wt_status *s, int uncommitt
 		argv_array_push(&argv, s->amend ? "HEAD^" : "HEAD");
 
 	sm_summary.argv = argv.argv;
-	sm_summary.env = env.argv;
 	sm_summary.git_cmd = 1;
 	sm_summary.no_stdin = 1;
 	fflush(s->fp);
 	sm_summary.out = -1;
 
 	run_command(&sm_summary);
-	argv_array_clear(&env);
 	argv_array_clear(&argv);
 
 	len = strbuf_read(&cmd_stdout, sm_summary.out, 1024);