ash: make evaltree save/restore int suppression depth.

 Hopefully this fixes bug 189. Not confirmed by users yet.

function                                             old     new   delta
evaltree                                             809     842     +33
evalvar                                             1374    1376      +2

1 files changed, 78 insertions, 38 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 9bb1d421e..a8383d805 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -30,7 +30,7 @@
  */
 
 /*
- * The follow should be set to reflect the type of system you have:
+ * The following should be set to reflect the type of system you have:
  *      JOBS -> 1 if you have Berkeley job control, 0 otherwise.
  *      define SYSV if you are running under System V.
  *      define DEBUG=1 to compile in debugging ('set -o debug' to turn on)
@@ -40,6 +40,11 @@
  * a quit signal will generate a core dump.
  */
 #define DEBUG 0
+/* Tweak debug output verbosity here */
+#define DEBUG_TIME 0
+#define DEBUG_PID 1
+#define DEBUG_SIG 1
+
 #define PROFILE 0
 
 #define IFS_BROKEN
@@ -47,9 +52,9 @@
 #define JOBS ENABLE_ASH_JOB_CONTROL
 
 #if DEBUG
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE
-#endif
+# ifndef _GNU_SOURCE
+#  define _GNU_SOURCE
+# endif
 #endif
 
 #include "busybox.h" /* for applet_names */
@@ -71,11 +76,11 @@
 #endif
 
 #ifndef PIPE_BUF
-#define PIPE_BUF 4096           /* amount of buffering in a pipe */
+# define PIPE_BUF 4096           /* amount of buffering in a pipe */
 #endif
 
 #if defined(__uClinux__)
-#error "Do not even bother, ash will not run on NOMMU machine"
+# error "Do not even bother, ash will not run on NOMMU machine"
 #endif
 
 
@@ -86,14 +91,6 @@
 #define CMDTABLESIZE 31         /* should be prime */
 
 
-/* ============ Misc helpers */
-
-#define xbarrier() do { __asm__ __volatile__ ("": : :"memory"); } while (0)
-
-/* C99 says: "char" declaration may be signed or unsigned by default */
-#define signed_char2int(sc) ((int)((signed char)sc))
-
-
 /* ============ Shell options */
 
 static const char *const optletters_optnames[] = {
@@ -257,7 +254,24 @@ extern struct globals_misc *const ash_ptr_to_globals_misc;
 } while (0)
 
 
+/* ============ DEBUG */
+#if DEBUG
+static void trace_printf(const char *fmt, ...);
+static void trace_vprintf(const char *fmt, va_list va);
+# define TRACE(param)    trace_printf param
+# define TRACEV(param)   trace_vprintf param
+#else
+# define TRACE(param)
+# define TRACEV(param)
+#endif
+
+
 /* ============ Utility functions */
+#define xbarrier() do { __asm__ __volatile__ ("": : :"memory"); } while (0)
+
+/* C99 say: "char" declaration may be signed or unsigned by default */
+#define signed_char2int(sc) ((int)(signed char)(sc))
+
 static int isdigit_str9(const char *str)
 {
         int maxlen = 9 + 1; /* max 9 digits: 999999999 */
@@ -296,6 +310,12 @@ raise_exception(int e)
         exception_type = e;
         longjmp(exception_handler->loc, 1);
 }
+#if DEBUG
+#define raise_exception(e) do { \
+        TRACE(("raising exception %d on line %d\n", (e), __LINE__)); \
+        raise_exception(e); \
+} while (0)
+#endif
 
 /*
  * Called from trap.c when a SIGINT is received.  (If the user specifies
@@ -328,6 +348,12 @@ raise_interrupt(void)
         raise_exception(ex_type);
         /* NOTREACHED */
 }
+#if DEBUG
+#define raise_interrupt() do { \
+        TRACE(("raising interrupt on line %d\n", __LINE__)); \
+        raise_interrupt(); \
+} while (0)
+#endif
 
 #if ENABLE_ASH_OPTIMIZE_FOR_SIZE
 static void
@@ -346,7 +372,9 @@ force_int_on(void)
                 raise_interrupt();
 }
 #define FORCE_INT_ON force_int_on()
-#else
+
+#else /* !ASH_OPTIMIZE_FOR_SIZE */
+
 #define INT_ON do { \
         xbarrier(); \
         if (--suppressint == 0 && intpending) \
@@ -358,7 +386,7 @@ force_int_on(void)
         if (intpending) \
                 raise_interrupt(); \
 } while (0)
-#endif /* ASH_OPTIMIZE_FOR_SIZE */
+#endif /* !ASH_OPTIMIZE_FOR_SIZE */
 
 #define SAVE_INT(v) ((v) = suppressint)
 
@@ -666,6 +694,12 @@ trace_printf(const char *fmt, ...)
 
         if (debug != 1)
                 return;
+        if (DEBUG_TIME)
+                fprintf(tracefile, "%u ", (int) time(NULL));
+        if (DEBUG_PID)
+                fprintf(tracefile, "[%u] ", (int) getpid());
+        if (DEBUG_SIG)
+                fprintf(tracefile, "pending s:%d i:%d(supp:%d) ", pendingsig, intpending, suppressint);
         va_start(va, fmt);
         vfprintf(tracefile, fmt, va);
         va_end(va);
@@ -676,6 +710,12 @@ trace_vprintf(const char *fmt, va_list va)
 {
         if (debug != 1)
                 return;
+        if (DEBUG_TIME)
+                fprintf(tracefile, "%u ", (int) time(NULL));
+        if (DEBUG_PID)
+                fprintf(tracefile, "[%u] ", (int) getpid());
+        if (DEBUG_SIG)
+                fprintf(tracefile, "pending s:%d i:%d(supp:%d) ", pendingsig, intpending, suppressint);
         vfprintf(tracefile, fmt, va);
 }
 
@@ -980,14 +1020,6 @@ showtree(union node *n)
         shtree(n, 1, NULL, stdout);
 }
 
-#define TRACE(param)    trace_printf param
-#define TRACEV(param)   trace_vprintf param
-
-#else
-
-#define TRACE(param)
-#define TRACEV(param)
-
 #endif /* DEBUG */
 
 
@@ -7951,6 +7983,7 @@ dotrap(void)
         pendingsig = 0;
         xbarrier();
 
+        TRACE(("dotrap entered\n"));
         for (sig = 1, g = gotsig; sig < NSIG; sig++, g++) {
                 int want_exexit;
                 char *t;
@@ -7962,15 +7995,20 @@ dotrap(void)
                  * don't upset it by resetting gotsig[SIGINT-1] */
                 if (sig == SIGINT && !t)
                         continue;
+
+                TRACE(("sig %d is active, will run handler '%s'\n", sig, t));
                 *g = 0;
                 if (!t)
                         continue;
                 want_exexit = evalstring(t, SKIPEVAL);
                 exitstatus = savestatus;
-                if (want_exexit)
+                if (want_exexit) {
+                        TRACE(("dotrap returns %d\n", skip));
                         return want_exexit;
+                }
         }
 
+        TRACE(("dotrap returns 0\n"));
         return 0;
 }
 
@@ -7997,22 +8035,27 @@ evaltree(union node *n, int flags)
         int checkexit = 0;
         void (*evalfn)(union node *, int);
         int status;
+        int int_level;
+
+        SAVE_INT(int_level);
 
         if (n == NULL) {
                 TRACE(("evaltree(NULL) called\n"));
                 goto out1;
         }
-        TRACE(("pid %d, evaltree(%p: %d, %d) called\n",
-                        getpid(), n, n->type, flags));
+        TRACE(("evaltree(%p: %d, %d) called\n", n, n->type, flags));
 
         exception_handler = &jmploc;
         {
                 int err = setjmp(jmploc.loc);
                 if (err) {
                         /* if it was a signal, check for trap handlers */
-                        if (exception_type == EXSIG)
+                        if (exception_type == EXSIG) {
+                                TRACE(("exception %d (EXSIG) in evaltree, err=%d\n", exception, err));
                                 goto out;
+                        }
                         /* continue on the way out */
+                        TRACE(("exception %d in evaltree, propagating err=%d\n", exception, err));
                         exception_handler = savehandler;
                         longjmp(exception_handler->loc, err);
                 }
@@ -8095,7 +8138,8 @@ evaltree(union node *n, int flags)
                 if (exitstatus == 0) {
                         n = n->nif.ifpart;
                         goto evaln;
-                } else if (n->nif.elsepart) {
+                }
+                if (n->nif.elsepart) {
                         n = n->nif.elsepart;
                         goto evaln;
                 }
@@ -8121,6 +8165,9 @@ evaltree(union node *n, int flags)
  exexit:
                 raise_exception(EXEXIT);
         }
+
+        RESTORE_INT(int_level);
+        TRACE(("leaving evaltree (no interrupts)\n"));
 }
 
 #if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
@@ -8998,6 +9045,7 @@ evalcommand(union node *cmd, int flags)
                         if (forkshell(jp, cmd, FORK_FG) != 0) {
                                 exitstatus = waitforjob(jp);
                                 INT_ON;
+                                TRACE(("forked child exited with %d\n", exitstatus));
                                 break;
                         }
                         FORCE_INT_ON;
@@ -13762,7 +13810,7 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
         exception_handler = &jmploc;
 #if DEBUG
         opentrace();
-        trace_puts("Shell args: ");
+        TRACE(("Shell args: "));
         trace_puts_args(argv);
 #endif
         rootpid = getpid();
@@ -13847,14 +13895,6 @@ int ash_main(int argc UNUSED_PARAM, char **argv)
         /* NOTREACHED */
 }
 
-#if DEBUG
-const char *applet_name = "debug stuff usage";
-int main(int argc, char **argv)
-{
-        return ash_main(argc, argv);
-}
-#endif
-
 
 /*-
  * Copyright (c) 1989, 1991, 1993, 1994