ash: implement set -o pipefail (conditional on bash compat). +39 bytes

Signed-off-by: Michael Abbott <michael@araneidae.co.uk>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 21 insertions, 3 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 65d41cc5b..e7cf7975f 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -101,6 +101,9 @@ static const char *const optletters_optnames[] = {
         "b"   "notify",
         "u"   "nounset",
         "\0"  "vi",
+#if ENABLE_ASH_BASH_COMPAT
+        "\0"  "pipefail"
+#endif
 #if DEBUG
         ,"\0"  "nolog"
         ,"\0"  "debug"
@@ -178,9 +181,14 @@ struct globals_misc {
 #define bflag optlist[11]
 #define uflag optlist[12]
 #define viflag optlist[13]
+#if ENABLE_ASH_BASH_COMPAT
+# define pipefail optlist[14]
+#else
+# define pipefail 0
+#endif
 #if DEBUG
-#define nolog optlist[14]
-#define debug optlist[15]
+# define nolog optlist[14 + ENABLE_ASH_BASH_COMPAT]
+# define debug optlist[15 + ENABLE_ASH_BASH_COMPAT]
 #endif
 
         /* trap handler commands */
@@ -3999,13 +4007,23 @@ jobscmd(int argc UNUSED_PARAM, char **argv)
 }
 #endif /* JOBS */
 
+/* Called only on finished or stopped jobs (no members are running) */
 static int
 getstatus(struct job *job)
 {
         int status;
         int retval;
+        struct procstat *ps;
+
+        /* Fetch last member's status */
+        ps = job->ps + job->nprocs - 1;
+        status = ps->ps_status;
+        if (pipefail) {
+                /* "set -o pipefail" mode: use last _nonzero_ status */
+                while (status == 0 && --ps >= job->ps)
+                        status = ps->ps_status;
+        }
 
-        status = job->ps[job->nprocs - 1].ps_status;
         retval = WEXITSTATUS(status);
         if (!WIFEXITED(status)) {
 #if JOBS