Implement pthread_atfork()

If threads are being used, then fork() will now acquire and release and
runtime locks so that fork() may be safely used from threads. This also
makes vfork() thread safe, because pthread mutexes will do nothing when
the process is a child of vfork(). More torture tests have been written
to confirm this all works like a charm. Additionally:

- Invent hexpcpy() api
- Rename nsync_malloc_() to kmalloc()
- Complete posix named semaphore implementation
- Make pthread_create() asynchronous signal safe
- Add rm, rmdir, and touch to command interpreter builtins
- Invent sigisprecious() and modify sigset functions to use it
- Add unit tests for posix_spawn() attributes and fix its bugs

One unresolved problem is the reclaiming of *NSYNC waiter memory in the
forked child processes, within apps which have threads waiting on locks
This commit is contained in:
Justine Tunney 2022-10-16 12:05:08 -07:00
parent 64c284003d
commit 60cb435cb4
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
124 changed files with 2169 additions and 718 deletions

View file

@ -11,19 +11,19 @@
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
#define kAutomapStart 0x100080040000
#define kAutomapSize (kMemtrackStart - kAutomapStart)
#define kMemtrackStart 0x1fe7fffc0000
#define kMemtrackSize (0x1ffffffc0000 - kMemtrackStart)
#define kFixedmapStart 0x300000040000
#define kFixedmapSize (0x400000040000 - kFixedmapStart)
#define kMemtrackFdsStart 0x6fe000040000
#define kMemtrackFdsSize (0x6feffffc0000 - kMemtrackFdsStart)
#define kMemtrackZiposStart 0x6fd000040000
#define kMemtrackZiposSize (0x6fdffffc0000 - kMemtrackZiposStart)
#define kMemtrackNsyncStart 0x6fc000040000
#define kMemtrackNsyncSize (0x6fcffffc0000 - kMemtrackNsyncStart)
#define kMemtrackGran (!IsAsan() ? FRAMESIZE : FRAMESIZE * 8)
#define kAutomapStart 0x100080040000
#define kAutomapSize (kMemtrackStart - kAutomapStart)
#define kMemtrackStart 0x1fe7fffc0000
#define kMemtrackSize (0x1ffffffc0000 - kMemtrackStart)
#define kFixedmapStart 0x300000040000
#define kFixedmapSize (0x400000040000 - kFixedmapStart)
#define kMemtrackFdsStart 0x6fe000040000
#define kMemtrackFdsSize (0x6feffffc0000 - kMemtrackFdsStart)
#define kMemtrackZiposStart 0x6fd000040000
#define kMemtrackZiposSize (0x6fdffffc0000 - kMemtrackZiposStart)
#define kMemtrackKmallocStart 0x6fc000040000
#define kMemtrackKmallocSize (0x6fcffffc0000 - kMemtrackKmallocStart)
#define kMemtrackGran (!IsAsan() ? FRAMESIZE : FRAMESIZE * 8)
struct MemoryInterval {
int x;
@ -47,6 +47,7 @@ extern struct MemoryIntervals _mmi;
void __mmi_lock(void);
void __mmi_unlock(void);
void __mmi_funlock(void);
bool IsMemtracked(int, int);
void PrintSystemMappings(int);
unsigned FindMemoryInterval(const struct MemoryIntervals *, int) nosideeffect;
@ -95,9 +96,9 @@ forceinline pureconst bool IsZiposFrame(int x) {
x <= (int)((kMemtrackZiposStart + kMemtrackZiposSize - 1) >> 16);
}
forceinline pureconst bool IsNsyncFrame(int x) {
return (int)(kMemtrackNsyncStart >> 16) <= x &&
x <= (int)((kMemtrackNsyncStart + kMemtrackNsyncSize - 1) >> 16);
forceinline pureconst bool IsKmallocFrame(int x) {
return (int)(kMemtrackKmallocStart >> 16) <= x &&
x <= (int)((kMemtrackKmallocStart + kMemtrackKmallocSize - 1) >> 16);
}
forceinline pureconst bool IsShadowFrame(int x) {