fault signal

diff --git a/fault-signal/.gitignore b/fault-signal/.gitignore
new file mode 100644 (file)
index 0000000..89547ba
--- /dev/null
+++ b/fault-signal/.gitignore
@@ -0,0 +1 @@
+log.txt
\ No newline at end of file

diff --git a/fault-signal/2508-02.xyz.md b/fault-signal/2508-02.xyz.md
new file mode 100644 (file)
index 0000000..8094ea1
--- /dev/null
+++ b/fault-signal/2508-02.xyz.md
@@ -0,0 +1,143 @@
+#
+
+```shell
+...
+[2025-08-08 16:13:45] counting: 2464200
+[2025-08-08 16:13:45] counting: 2464300
+[2025-08-08 16:13:45] counting: 2464400
+[2025-08-08 16:13:45] counting: 2464500
+[2025-08-08 16:13:45] counting: 2464600
+[2025-08-08 16:13:45] counting: 2464700
+[2025-08-08 16:13:45] counting: 2464800
+[2025-08-08 16:13:45] counting: 2464900
+[2025-08-08 16:13:45] counting: 2465000
+[2025-08-08 16:13:45] counting: 2465100
+[2025-08-08 16:13:45] counting: 2465200
+[2025-08-08 16:13:45] counting: 2465300
+[2025-08-08 16:13:45] counting: 2465400
+[2025-08-08 16:13:45] counting: 2465500
+[2025-08-08 16:13:45] counting: 2465600
+[2025-08-08 16:13:45] counting: 2465700
+^Csig received 2: 2465790
+
+```
+
+
+#
+
+```shell
+thy@thy-Z370-HD3:~/hack/linux/linuxyz/fault-signal$ sudo pgrep test.out 
+3276908
+```
+
+#
+
+```shell
+thy@thy-Z370-HD3:~/hack/linux/linuxyz/fault-signal$ sudo gdb -p 3276908
+```
+
+#
+
+```shell
+[Thread debugging using libthread_db enabled]
+Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
+futex_wait (private=0, expected=2, futex_word=0x76e64d60a3e0 <tzset_lock>)
+    at ../sysdeps/nptl/futex-internal.h:146
+
+warning: 146    ../sysdeps/nptl/futex-internal.h: No such file or directory
+(gdb) backtrace
+
+```
+
+```shell
+#0  futex_wait (private=0, expected=2, futex_word=0x76e64d60a3e0 <tzset_lock>)
+    at ../sysdeps/nptl/futex-internal.h:146
+#1  __GI___lll_lock_wait_private (futex=futex@entry=0x76e64d60a3e0 <tzset_lock>)
+    at ./nptl/lowlevellock.c:34
+#2  0x000076e64d4e1314 in __tz_convert (timer=1754637395, use_localtime=1, tp=0x7ffdd33b4830)
+    at ./time/tzset.c:572
+#3  0x0000000000401253 in ch_handler (sig=2) at main.c:17
+#4  <signal handler called>
+#5  0x000076e64d4955e7 in __GI__IO_default_uflow (fp=<optimized out>) at ./libio/genops.c:366
+#6  0x000076e64d46d9f1 in __vfscanf_internal (s=s@entry=0x7ffdd33b5650, 
+    format=format@entry=0x76e64d5cc9f9 "%hu%n:%hu%n:%hu%n", argptr=argptr@entry=0x7ffdd33b5638, 
+    mode_flags=mode_flags@entry=6) at ./stdio-common/vfscanf-internal.c:1881
+#7  0x000076e64d45fc2c in __GI___isoc23_sscanf (s=s@entry=0x3cd63601 "9", 
+    format=format@entry=0x76e64d5cc9f9 "%hu%n:%hu%n:%hu%n") at ./stdio-common/isoc23_sscanf.c:31
+#8  0x000076e64d4dffdc in parse_offset (tzp=tzp@entry=0x7ffdd33b5898, whichrule=whichrule@entry=0)
+    at ./time/tzset.c:207
+#9  0x000076e64d4e0532 in __tzset_parse_tz (tz=<optimized out>) at ./time/tzset.c:328
+#10 0x000076e64d4e2819 in __tzfile_compute (timer=timer@entry=1754637395, 
+    use_localtime=use_localtime@entry=1, leap_correct=leap_correct@entry=0x7ffdd33b5930, 
+    leap_hit=leap_hit@entry=0x7ffdd33b592c, tp=tp@entry=0x7ffdd33b5a00) at ./time/tzfile.c:634
+#11 0x000076e64d4e11b2 in __tz_convert (timer=1754637395, use_localtime=1, tp=0x7ffdd33b5a00)
+    at ./time/tzset.c:580
+#12 0x0000000000401375 in main (argc=1, argv=0x7ffdd33b5b68) at main.c:33
+```
+
+#
+
+```c
+
+/* Return the `struct tm' representation of *T in local time,
+   using *TP to store the result.  */
+struct tm *
+__localtime64_r (const __time64_t *t, struct tm *tp)
+{
+  return __tz_convert (*t, 1, tp);
+}
+
+/* Provide a 32-bit variant if needed.  */
+
+#if __TIMESIZE != 64
+
+struct tm *
+__localtime_r (const time_t *t, struct tm *tp)
+{
+  __time64_t t64 = *t;
+  return __localtime64_r (&t64, tp);
+}
+libc_hidden_def (__localtime64_r)
+
+#endif
+
+weak_alias (__localtime_r, localtime_r)
+
+```
+
+#
+
+```c
+
+/* Return the `struct tm' representation of TIMER in the local timezone.
+   Use local time if USE_LOCALTIME is nonzero, UTC otherwise.  */
+struct tm *
+__tz_convert (__time64_t timer, int use_localtime, struct tm *tp)
+{
+  long int leap_correction;
+  int leap_extra_secs;
+
+  __libc_lock_lock (tzset_lock);
+
+  /* Update internal database according to current TZ setting.
+     POSIX.1 8.3.7.2 says that localtime_r is not required to set tzname.
+     This is a good idea since this allows at least a bit more parallelism.  */
+  tzset_internal (tp == &_tmbuf && use_localtime);
+
+  if (__use_tzfile)
+    __tzfile_compute (timer, use_localtime, &leap_correction,
+                     &leap_extra_secs, tp);
+  else
+    {
+      if (! __offtime (timer, 0, tp))
+       tp = NULL;
+      else
+       __tz_compute (timer, tp, use_localtime);
+      leap_correction = 0L;
+      leap_extra_secs = 0;
+    }
+
+  __libc_lock_unlock (tzset_lock);
+
+...
+```
\ No newline at end of file

diff --git a/fault-signal/Makefile b/fault-signal/Makefile
new file mode 100644 (file)
index 0000000..f67dc7d
--- /dev/null
+++ b/fault-signal/Makefile
@@ -0,0 +1,7 @@
+all:
+
+       gcc -g -o test.out main.c
+
+clean:
+
+       rm -rf *.o *.out
\ No newline at end of file

diff --git a/fault-signal/main.c b/fault-signal/main.c
new file mode 100644 (file)
index 0000000..6501a9f
--- /dev/null
+++ b/fault-signal/main.c
@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <signal.h>
+#include <unistd.h>
+#include <pthread.h>
+
+
+int counter = 0;
+
+void ch_handler(int sig){
+    struct tm tm_info;
+    char timebuf[128] = {0};
+    time_t ch_timer = time(NULL);
+    printf("sig received %d: %d\n", sig, counter);
+       localtime_r(&ch_timer, &tm_info);
+       strftime(timebuf, 128, "%Y-%m-%d %H:%M:%S", &tm_info);
+       printf("[%s] signal handled: %d\n", timebuf, counter);
+}
+
+
+int main(int argc, char** argv){
+
+       time_t timer;
+       struct tm tm_info;
+    pthread_t tid;
+       char timebuf[128] = {0};
+
+       signal(SIGINT, ch_handler);
+       while(1){
+        timer = time(NULL);
+               localtime_r(&timer, &tm_info);
+        strftime(timebuf, 128, "%Y-%m-%d %H:%M:%S", &tm_info);
+        counter += 1;
+        if(counter % 100 == 0){
+            printf("[%s] counting: %d\n", timebuf, counter);
+        }
+       }
+
+       return 0;
+}