From d5c2daef10de69002c6ab34bdcf1b707da2097b6 Mon Sep 17 00:00:00 2001
From: Wichert Akkerman <wichert@deephackmode.org>
Date: Thu, 12 Apr 2001 09:10:24 +0000
Subject: [PATCH] switch to using /proc/<pid>/status on Linux

---
 signal.c | 96 +++++++++++++++++++++++++++++++++-----------------------
 1 file changed, 56 insertions(+), 40 deletions(-)

diff --git a/signal.c b/signal.c
index 6051d8ff..4a676a19 100644
--- a/signal.c
+++ b/signal.c
@@ -378,40 +378,81 @@ int sig;
 #ifdef LINUX
 	int sfd;
 	char sname[32];
-	char buf[1024];
+	char buf[2048];
 	char *s;
 	int i;
-	unsigned int signalled, blocked, ignored, caught;
+	/* We also need to handle RT signals */
+	unsigned long long signalled, blocked, ignored, caught;
+#endif
+#ifdef SVR4
+	/*
+	 * Since procfs doesn't interfere with wait I think it is safe
+	 * to punt on this question.  If not, the information is there.
+	 */
+	return 1;
+#else /* !SVR4 */
+	switch (sig) {
+	case SIGCONT:
+	case SIGSTOP:
+	case SIGTSTP:
+	case SIGTTIN:
+	case SIGTTOU:
+	case SIGCHLD:
+	case SIGIO:
+#if defined(SIGURG) && SIGURG != SIGIO
+	case SIGURG:
+#endif
+	case SIGWINCH:
+		/* Gloria Gaynor says ... */
+		return 1;
+	default:
+		break;
+	}
+#endif /* !SVR4 */
+#ifdef LINUX
 
 	/* This is incredibly costly but it's worth it. */
-	sprintf(sname, "/proc/%d/stat", tcp->pid);
+	/* NOTE: LinuxThreads internally uses SIGRTMIN, SIGRTMIN + 1 and
+	   SIGRTMIN + 2, so we can't use the obsolete /proc/%d/stat which
+	   doesn't handle real-time signals). */
+	sprintf(sname, "/proc/%d/status", tcp->pid);
 	if ((sfd = open(sname, O_RDONLY)) == -1) {
 		perror(sname);
 		return 1;
 	}
-	i = read(sfd, buf, 1024);
+	i = read(sfd, buf, sizeof(buf));
 	buf[i] = '\0';
 	close(sfd);
 	/*
-	 * Skip the extraneous fields. This loses if the
+	 * Skip the extraneous fields. We need to skip
 	 * command name has any spaces in it.  So be it.
 	 */
-	for (i = 0, s = buf; i < 30; i++) {
-		while (*++s != ' ') {
-			if (!*s)
-				break;
-		}
-	}
-	if (sscanf(s, "%u%u%u%u",
-		   &signalled, &blocked, &ignored, &caught) != 4) {
-		fprintf(stderr, "/proc/pid/stat format error\n");
+	s = strstr(buf, "SigPnd:\t");
+
+	if (!s)
+	{
+		fprintf(stderr, "/proc/pid/status format error\n");
 		return 1;
 	}
+
+	while (*s && *s++ != '\t')
+		;
+	s += sscanf(s, "%qx", &signalled);
+	while (*s && *s++ != '\t')
+		;
+	s += sscanf(s, "%qx", &blocked);
+	while (*s && *s++ != '\t')
+		;
+	s += sscanf(s, "%qx", &ignored);
+	while (*s && *s++ != '\t')
+		;
+	s += sscanf(s, "%qx", &caught);
+
 #ifdef DEBUG
 	fprintf(stderr, "sigs: %08x %08x %08x %08x\n",
 		signalled, blocked, ignored, caught);
 #endif
-	if ((ignored & sigmask(sig)) || (caught & sigmask(sig)))
+	if ((ignored & (1ULL << sig)) || (caught & (1ULL << sig)))
 		return 1;
 #endif /* LINUX */
 
@@ -426,32 +467,7 @@ int sig;
 		return 1;
 #endif /* SUNOS4 */
 
-#ifdef SVR4
-	/*
-	 * Since procfs doesn't interfere with wait I think it is safe
-	 * to punt on this question.  If not, the information is there.
-	 */
-	return 1;
-#else /* !SVR4 */
-	switch (sig) {
-	case SIGCONT:
-	case SIGSTOP:
-	case SIGTSTP:
-	case SIGTTIN:
-	case SIGTTOU:
-	case SIGCHLD:
-	case SIGIO:
-#if defined(SIGURG) && SIGURG != SIGIO
-	case SIGURG:
-#endif
-	case SIGWINCH:
-		/* Gloria Gaynor says ... */
-		return 1;
-	default:
-		break;
-	}
 	return 0;
-#endif /* !SVR4 */
 }
 
 #if defined(SUNOS4) || defined(FREEBSD)
-- 
2.40.0