1 files changed, 119 insertions, 0 deletions
diff --git a/exec_cmd.c b/exec_cmd.c
new file mode 100644
index 0000000000..e189caca62
--- /dev/null
+++ b/exec_cmd.c
@@ -0,0 +1,119 @@
+#include "cache.h"
+#include "exec_cmd.h"
+#include "quote.h"
+#define MAX_ARGS	32
+
+extern char **environ;
+static const char *builtin_exec_path = GIT_EXEC_PATH;
+static const char *argv_exec_path;
+
+void git_set_argv_exec_path(const char *exec_path)
+{
+	argv_exec_path = exec_path;
+}
+
+
+/* Returns the highest-priority, location to look for git programs. */
+const char *git_exec_path(void)
+{
+	const char *env;
+
+	if (argv_exec_path)
+		return argv_exec_path;
+
+	env = getenv(EXEC_PATH_ENVIRONMENT);
+	if (env && *env) {
+		return env;
+	}
+
+	return builtin_exec_path;
+}
+
+static void add_path(struct strbuf *out, const char *path)
+{
+	if (path && *path) {
+		if (is_absolute_path(path))
+			strbuf_addstr(out, path);
+		else
+			strbuf_addstr(out, make_absolute_path(path));
+
+		strbuf_addch(out, ':');
+	}
+}
+
+void setup_path(const char *cmd_path)
+{
+	const char *old_path = getenv("PATH");
+	struct strbuf new_path;
+
+	strbuf_init(&new_path, 0);
+
+	add_path(&new_path, argv_exec_path);
+	add_path(&new_path, getenv(EXEC_PATH_ENVIRONMENT));
+	add_path(&new_path, builtin_exec_path);
+	add_path(&new_path, cmd_path);
+
+	if (old_path)
+		strbuf_addstr(&new_path, old_path);
+	else
+		strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
+
+	setenv("PATH", new_path.buf, 1);
+
+	strbuf_release(&new_path);
+}
+
+int execv_git_cmd(const char **argv)
+{
+	struct strbuf cmd;
+	const char *tmp;
+
+	strbuf_init(&cmd, 0);
+	strbuf_addf(&cmd, "git-%s", argv[0]);
+
+	/*
+	 * argv[0] must be the git command, but the argv array
+	 * belongs to the caller, and may be reused in
+	 * subsequent loop iterations. Save argv[0] and
+	 * restore it on error.
+	 */
+	tmp = argv[0];
+	argv[0] = cmd.buf;
+
+	trace_argv_printf(argv, "trace: exec:");
+
+	/* execvp() can only ever return if it fails */
+	execvp(cmd.buf, (char **)argv);
+
+	trace_printf("trace: exec failed: %s\n", strerror(errno));
+
+	argv[0] = tmp;
+
+	strbuf_release(&cmd);
+
+	return -1;
+}
+
+
+int execl_git_cmd(const char *cmd,...)
+{
+	int argc;
+	const char *argv[MAX_ARGS + 1];
+	const char *arg;
+	va_list param;
+
+	va_start(param, cmd);
+	argv[0] = cmd;
+	argc = 1;
+	while (argc < MAX_ARGS) {
+		arg = argv[argc++] = va_arg(param, char *);
+		if (!arg)
+			break;
+	}
+	va_end(param);
+	if (MAX_ARGS <= argc)
+		return error("too many args to run %s", cmd);
+
+	argv[argc] = NULL;
+	return execv_git_cmd(argv);
+}