Mercurial > hg > nginx-quic
view src/os/unix/ngx_pthread_thread.c @ 5356:acd51b0f6fd4
Disable symlinks: use O_PATH to open path components.
It was introduced in Linux 2.6.39, glibc 2.14 and allows to obtain
file descriptors without actually opening files. Thus made it possible
to traverse path with openat() syscalls without the need to have read
permissions for path components. It is effectively emulates O_SEARCH
which is missing on Linux.
O_PATH is used in combination with O_RDONLY. The last one is ignored
if O_PATH is used, but it allows nginx to not fail when it was built on
modern system (i.e. glibc 2.14+) and run with a kernel older than 2.6.39.
Then O_PATH is unknown to the kernel and ignored, while O_RDONLY is used.
Sadly, fstat() is not working with O_PATH descriptors till Linux 3.6.
As a workaround we fallback to fstatat() with the AT_EMPTY_PATH flag
that was introduced at the same time as O_PATH.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Mon, 02 Sep 2013 08:07:59 +0400 |
parents | d620f497c50f |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> static ngx_uint_t nthreads; static ngx_uint_t max_threads; static pthread_attr_t thr_attr; ngx_err_t ngx_create_thread(ngx_tid_t *tid, ngx_thread_value_t (*func)(void *arg), void *arg, ngx_log_t *log) { int err; if (nthreads >= max_threads) { ngx_log_error(NGX_LOG_CRIT, log, 0, "no more than %ui threads can be created", max_threads); return NGX_ERROR; } err = pthread_create(tid, &thr_attr, func, arg); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, log, err, "pthread_create() failed"); return err; } ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0, "thread is created: " NGX_TID_T_FMT, *tid); nthreads++; return err; } ngx_int_t ngx_init_threads(int n, size_t size, ngx_cycle_t *cycle) { int err; max_threads = n; err = pthread_attr_init(&thr_attr); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, err, "pthread_attr_init() failed"); return NGX_ERROR; } err = pthread_attr_setstacksize(&thr_attr, size); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, err, "pthread_attr_setstacksize() failed"); return NGX_ERROR; } ngx_threaded = 1; return NGX_OK; } ngx_mutex_t * ngx_mutex_init(ngx_log_t *log, ngx_uint_t flags) { int err; ngx_mutex_t *m; m = ngx_alloc(sizeof(ngx_mutex_t), log); if (m == NULL) { return NULL; } m->log = log; err = pthread_mutex_init(&m->mutex, NULL); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, m->log, err, "pthread_mutex_init() failed"); return NULL; } return m; } void ngx_mutex_destroy(ngx_mutex_t *m) { int err; err = pthread_mutex_destroy(&m->mutex); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, m->log, err, "pthread_mutex_destroy(%p) failed", m); } ngx_free(m); } void ngx_mutex_lock(ngx_mutex_t *m) { int err; if (!ngx_threaded) { return; } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "lock mutex %p", m); err = pthread_mutex_lock(&m->mutex); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, m->log, err, "pthread_mutex_lock(%p) failed", m); ngx_abort(); } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "mutex %p is locked", m); return; } ngx_int_t ngx_mutex_trylock(ngx_mutex_t *m) { int err; if (!ngx_threaded) { return NGX_OK; } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "try lock mutex %p", m); err = pthread_mutex_trylock(&m->mutex); if (err == NGX_EBUSY) { return NGX_AGAIN; } if (err != 0) { ngx_log_error(NGX_LOG_ALERT, m->log, err, "pthread_mutex_trylock(%p) failed", m); ngx_abort(); } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "mutex %p is locked", m); return NGX_OK; } void ngx_mutex_unlock(ngx_mutex_t *m) { int err; if (!ngx_threaded) { return; } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "unlock mutex %p", m); err = pthread_mutex_unlock(&m->mutex); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, m->log, err, "pthread_mutex_unlock(%p) failed", m); ngx_abort(); } ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "mutex %p is unlocked", m); return; } ngx_cond_t * ngx_cond_init(ngx_log_t *log) { int err; ngx_cond_t *cv; cv = ngx_alloc(sizeof(ngx_cond_t), log); if (cv == NULL) { return NULL; } cv->log = log; err = pthread_cond_init(&cv->cond, NULL); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cv->log, err, "pthread_cond_init() failed"); return NULL; } return cv; } void ngx_cond_destroy(ngx_cond_t *cv) { int err; err = pthread_cond_destroy(&cv->cond); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cv->log, err, "pthread_cond_destroy(%p) failed", cv); } ngx_free(cv); } ngx_int_t ngx_cond_wait(ngx_cond_t *cv, ngx_mutex_t *m) { int err; ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p wait", cv); err = pthread_cond_wait(&cv->cond, &m->mutex); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cv->log, err, "pthread_cond_wait(%p) failed", cv); return NGX_ERROR; } ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is waked up", cv); ngx_log_debug1(NGX_LOG_DEBUG_MUTEX, m->log, 0, "mutex %p is locked", m); return NGX_OK; } ngx_int_t ngx_cond_signal(ngx_cond_t *cv) { int err; ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p to signal", cv); err = pthread_cond_signal(&cv->cond); if (err != 0) { ngx_log_error(NGX_LOG_ALERT, cv->log, err, "pthread_cond_signal(%p) failed", cv); return NGX_ERROR; } ngx_log_debug1(NGX_LOG_DEBUG_CORE, cv->log, 0, "cv %p is signaled", cv); return NGX_OK; }