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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 | /* Linuxthreads - a simple clone()-based implementation of Posix */ /* threads for Linux. */ /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */ /* */ /* This program is free software; you can redistribute it and/or */ /* modify it under the terms of the GNU Library General Public License */ /* as published by the Free Software Foundation; either version 2 */ /* of the License, or (at your option) any later version. */ /* */ /* This program is distributed in the hope that it will be useful, */ /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ /* GNU Library General Public License for more details. */ /* mods for uClibc: removed strong alias and defined funcs properly */ /* The "atfork" stuff */ #include <errno.h> #ifdef __ARCH_USE_MMU__ #include <bits/uClibc_mutex.h> #include <stddef.h> #include <stdlib.h> #include <unistd.h> #include "pthread.h" #include "internals.h" struct handler_list { void (*handler)(void); struct handler_list * next; }; static pthread_mutex_t pthread_atfork_lock = PTHREAD_MUTEX_INITIALIZER; static struct handler_list * pthread_atfork_prepare = NULL; static struct handler_list * pthread_atfork_parent = NULL; static struct handler_list * pthread_atfork_child = NULL; #ifdef __MALLOC__ __UCLIBC_MUTEX_EXTERN(__malloc_heap_lock); __UCLIBC_MUTEX_EXTERN(__malloc_sbrk_lock); #ifdef __UCLIBC_UCLINUX_BROKEN_MUNMAP__ __UCLIBC_MUTEX_EXTERN(__malloc_mmb_heap_lock); #endif #elif defined(__MALLOC_STANDARD__) || defined(__MALLOC_SIMPLE__) __UCLIBC_MUTEX_EXTERN(__malloc_lock); #endif static void pthread_insert_list(struct handler_list ** list, void (*handler)(void), struct handler_list * newlist, int at_end) { if (handler == NULL) return; if (at_end) { while(*list != NULL) list = &((*list)->next); } newlist->handler = handler; newlist->next = *list; *list = newlist; } struct handler_list_block { struct handler_list prepare, parent, child; }; int pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void)) { struct handler_list_block * block = (struct handler_list_block *) malloc(sizeof(struct handler_list_block)); if (block == NULL) return ENOMEM; __pthread_mutex_lock(&pthread_atfork_lock); /* "prepare" handlers are called in LIFO */ pthread_insert_list(&pthread_atfork_prepare, prepare, &block->prepare, 0); /* "parent" handlers are called in FIFO */ pthread_insert_list(&pthread_atfork_parent, parent, &block->parent, 1); /* "child" handlers are called in FIFO */ pthread_insert_list(&pthread_atfork_child, child, &block->child, 1); __pthread_mutex_unlock(&pthread_atfork_lock); return 0; } /*strong_alias (__pthread_atfork, pthread_atfork)*/ static __inline__ void pthread_call_handlers(struct handler_list * list) { for (/*nothing*/; list != NULL; list = list->next) (list->handler)(); } void __pthread_once_fork_prepare(void); void __pthread_once_fork_child(void); void __pthread_once_fork_parent(void); static pid_t __fork(void) { pid_t pid; struct handler_list * prepare, * child, * parent; __pthread_mutex_lock(&pthread_atfork_lock); prepare = pthread_atfork_prepare; child = pthread_atfork_child; parent = pthread_atfork_parent; pthread_call_handlers(prepare); __pthread_once_fork_prepare(); #ifdef __MALLOC__ __pthread_mutex_lock(&__malloc_sbrk_lock); __pthread_mutex_lock(&__malloc_heap_lock); #ifdef __UCLIBC_UCLINUX_BROKEN_MUNMAP__ __pthread_mutex_lock(&__malloc_mmb_heap_lock); #endif #elif defined(__MALLOC_STANDARD__) || defined(__MALLOC_SIMPLE__) __pthread_mutex_lock(&__malloc_lock); #endif pid = __libc_fork(); if (pid == 0) { #if defined(__MALLOC_STANDARD__) || defined(__MALLOC_SIMPLE__) __libc_lock_init_recursive(__malloc_lock); #elif defined(__MALLOC__) #ifdef __UCLIBC_UCLINUX_BROKEN_MUNMAP__ __libc_lock_init_adaptive(__malloc_mmb_heap_lock); #endif __libc_lock_init_adaptive(__malloc_heap_lock); __libc_lock_init(__malloc_sbrk_lock); #endif __libc_lock_init_adaptive(pthread_atfork_lock); __pthread_reset_main_thread(); __fresetlockfiles(); __pthread_once_fork_child(); pthread_call_handlers(child); } else { #if defined(__MALLOC_STANDARD__) || defined(__MALLOC_SIMPLE__) __pthread_mutex_unlock(&__malloc_lock); #elif defined(__MALLOC__) #ifdef __UCLIBC_UCLINUX_BROKEN_MUNMAP__ __pthread_mutex_unlock(&__malloc_mmb_heap_lock); #endif __pthread_mutex_unlock(&__malloc_heap_lock); __pthread_mutex_unlock(&__malloc_sbrk_lock); #endif __pthread_mutex_unlock(&pthread_atfork_lock); __pthread_once_fork_parent(); pthread_call_handlers(parent); } return pid; } strong_alias(__fork,fork) strong_alias(__fork,vfork) #else /* We can't support pthread_atfork without MMU, since we don't have fork(), and we can't offer the correct semantics for vfork(). */ int pthread_atfork(void (*prepare)(void), void (*parent)(void), void (*child)(void)) { /* ENOMEM is probably pushing it a little bit. Take it as `no *virtual* memory' :-) */ errno = ENOMEM; return -1; } #endif |