Merge branch 'jk/maint-cleanup-after-exec-failure'

* jk/maint-cleanup-after-exec-failure:
git: use run_command() to execute dashed externals
run_command(): help callers distinguish errors
run_command(): handle missing command errors more gracefully
git: s/run_command/run_builtin/

diff --git a/git.c b/git.c
index 320cb435646361b9d542d22d1592f985008fb750..c2b181ed78daa4510f5cfb7bbff5b78f449f872a 100644 (file)
--- a/git.c
+++ b/git.c
@@ -2,6 +2,7 @@
 #include "exec_cmd.h"
 #include "cache.h"
 #include "quote.h"
+#include "run-command.h"
 
 const char git_usage_string[] =
        "git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate|--no-pager] [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE] [--help] COMMAND [ARGS]";
@@ -219,7 +220,7 @@ struct cmd_struct {
        int option;
 };
 
-static int run_command(struct cmd_struct *p, int argc, const char **argv)
+static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 {
        int status;
        struct stat st;
@@ -384,7 +385,7 @@ static void handle_internal_command(int argc, const char **argv)
                struct cmd_struct *p = commands+i;
                if (strcmp(p->cmd, cmd))
                        continue;
-               exit(run_command(p, argc, argv));
+               exit(run_builtin(p, argc, argv));
        }
 }
 
@@ -392,6 +393,7 @@ static void execv_dashed_external(const char **argv)
 {
        struct strbuf cmd = STRBUF_INIT;
        const char *tmp;
+       int status;
 
        strbuf_addf(&cmd, "git-%s", argv[0]);
 
@@ -406,10 +408,17 @@ static void execv_dashed_external(const char **argv)
 
        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));
+       /*
+        * if we fail because the command is not found, it is
+        * OK to return. Otherwise, we just pass along the status code.
+        */
+       status = run_command_v_opt(argv, 0);
+       if (status != -ERR_RUN_COMMAND_EXEC) {
+               if (IS_RUN_COMMAND_ERR(status))
+                       die("unable to run '%s'", argv[0]);
+               exit(-status);
+       }
+       errno = ENOENT; /* as if we called execvp */
 
        argv[0] = tmp;
 

diff --git a/run-command.c b/run-command.c
index db9ce59204aa4292e82ccd0aaf052cf4159cecdf..b05c734d05e99cd009a0df26f0fc95fa13ae6f25 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -118,7 +118,9 @@ int start_command(struct child_process *cmd)
                } else {
                        execvp(cmd->argv[0], (char *const*) cmd->argv);
                }
-               die("exec %s failed.", cmd->argv[0]);
+               trace_printf("trace: exec '%s' failed: %s\n", cmd->argv[0],
+                               strerror(errno));
+               exit(127);
        }
 #else
        int s0 = -1, s1 = -1, s2 = -1;  /* backups of stdin, stdout, stderr */
@@ -187,6 +189,7 @@ int start_command(struct child_process *cmd)
 #endif
 
        if (cmd->pid < 0) {
+               int err = errno;
                if (need_in)
                        close_pair(fdin);
                else if (cmd->in)
@@ -197,7 +200,9 @@ int start_command(struct child_process *cmd)
                        close(cmd->out);
                if (need_err)
                        close_pair(fderr);
-               return -ERR_RUN_COMMAND_FORK;
+               return err == ENOENT ?
+                       -ERR_RUN_COMMAND_EXEC :
+                       -ERR_RUN_COMMAND_FORK;
        }
 
        if (need_in)
@@ -236,9 +241,14 @@ static int wait_or_whine(pid_t pid)
                if (!WIFEXITED(status))
                        return -ERR_RUN_COMMAND_WAITPID_NOEXIT;
                code = WEXITSTATUS(status);
-               if (code)
+               switch (code) {
+               case 127:
+                       return -ERR_RUN_COMMAND_EXEC;
+               case 0:
+                       return 0;
+               default:
                        return -code;
-               return 0;
+               }
        }
 }
 

diff --git a/run-command.h b/run-command.h
index 0211e1d471d37a41f77098e8fff8a031fb26cb71..15e870a65eb037cd49d1e01251711915da06d260 100644 (file)
--- a/run-command.h
+++ b/run-command.h
@@ -10,6 +10,7 @@ enum {
        ERR_RUN_COMMAND_WAITPID_SIGNAL,
        ERR_RUN_COMMAND_WAITPID_NOEXIT,
 };
+#define IS_RUN_COMMAND_ERR(x) ((x) <= -ERR_RUN_COMMAND_FORK)
 
 struct child_process {
        const char **argv;