+++ /dev/null
-/*
- * Copyright (c) 2011 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-#include <assert.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/event.h>
-#include <asl.h>
-#include <asl_private.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <dispatch/dispatch.h>
-
-/* asl.c */
-__private_extern__ void asl_client_release(asl_client_t *asl);
-__private_extern__ asl_client_t *asl_client_retain(asl_client_t *asl);
-
-#define BUF_SIZE 512
-
-static dispatch_queue_t redirect_serial_q;
-static dispatch_group_t read_source_group;
-
-typedef struct {
- int level;
- asl_client_t *asl;
- asl_msg_t *msg;
-
- /* Buffered reading */
- char *buf;
- char *w;
-
- dispatch_source_t read_source;
-} asl_redirect_t;
-
-static asl_redirect_t *redirect_descriptors = NULL;
-static int n_redirect_descriptors = 0;
-
-/* Read from the FD until there is no more to read and redirect to ASL.
- * Preconditions:
- * 1: called from the appropriate serial queue for operating on
- * redirect_descriptors
- * 2: descriptor corresponds to a valid entry in redirect_descriptors
- *
- * Return values:
- * If the pipe is closed, EOF is returned regardless of how many bytes
- * were processed. If the pipe is still open, the number of read bytes
- * is returned.
- */
-static inline int _read_redirect(int descriptor, int flush) {
- int total_read = 0;
- int nbytes;
- asl_redirect_t *aslr = &redirect_descriptors[descriptor];
-
- while ((nbytes = read(descriptor, aslr->w, BUF_SIZE - (aslr->w - aslr->buf) - 1)) > 0) {
- char *s, *p;
-
- /* Increment our returned number read */
- total_read += nbytes;
-
- /* Increment our write location */
- aslr->w += nbytes;
- aslr->w[0] = '\0';
-
- /* One line at a time */
- for (p = aslr->buf; p < aslr->w; p = s + 1) {
- /* Find null or \n */
- for (s=p; *s && *s != '\n'; s++);
-
- if (*s == '\n') {
- *s='\0';
- }
-
- if (s < aslr->w || aslr->buf == p) {
- /* Either the first of multiple messages or one message which is larger than our buffer */
- asl_log((aslclient)aslr->asl, (aslmsg)aslr->msg, aslr->level, "%s", p);
- } else {
- /* We reached the end of the buffer, move this chunk to the start. */
- memmove(aslr->buf, p, BUF_SIZE - (p - aslr->buf));
- aslr->w = aslr->buf + (s - p);
- break;
- }
- }
-
- if (p == aslr->w) {
- /* Start writing at the beginning in the case where we cleared the buffer */
- aslr->w = aslr->buf;
- }
- }
-
- /* Flush if requested or we're at EOF */
- if (flush || nbytes == 0) {
- if (aslr->w > aslr->buf) {
- *aslr->w = '\0';
- asl_log((aslclient)aslr->asl, (aslmsg)aslr->msg, aslr->level, "%s", aslr->buf);
- }
- }
-
- if (nbytes == 0)
- return EOF;
- return total_read;
-}
-
-static void read_from_source(void *_source) {
- dispatch_source_t source = (dispatch_source_t)_source;
- int descriptor = dispatch_source_get_handle(source);
- if (_read_redirect(descriptor, 0) == EOF) {
- dispatch_source_cancel(source);
- }
-}
-
-static void cancel_source(void *_source) {
- dispatch_source_t source = (dispatch_source_t)_source;
- int descriptor = dispatch_source_get_handle(source);
- asl_redirect_t *aslr = &redirect_descriptors[descriptor];
-
- /* Flush the buffer */
- _read_redirect(descriptor, 1);
-
- close(descriptor);
-
- asl_client_release(aslr->asl);
- asl_msg_release(aslr->msg);
- free(aslr->buf);
-
- memset(aslr, 0, sizeof(*aslr));
- dispatch_release(source);
- dispatch_group_leave(read_source_group);
-}
-
-
-static void redirect_atexit(void) {
- int i;
-
- /* stdout is linebuffered, so flush the buffer */
- if (redirect_descriptors[STDOUT_FILENO].buf)
- fflush(stdout);
-
- /* Cancel all of our dispatch sources, so they flush to ASL */
- for (i=0; i < n_redirect_descriptors; i++)
- if (redirect_descriptors[i].read_source)
- dispatch_source_cancel(redirect_descriptors[i].read_source);
-
- /* Wait at least three seconds for our sources to flush to ASL */
- dispatch_group_wait(read_source_group, dispatch_time(DISPATCH_TIME_NOW, 3LL * NSEC_PER_SEC));
-}
-
-static void asl_descriptor_init(void *ctx __unused)
-{
- assert((redirect_descriptors = calloc(16, sizeof(*redirect_descriptors))) != NULL);
- n_redirect_descriptors = 16;
-
- redirect_serial_q = dispatch_queue_create("com.apple.asl-redirect", NULL);
- assert(redirect_serial_q != NULL);
-
- read_source_group = dispatch_group_create();
- assert(read_source_group != NULL);
-
- atexit(redirect_atexit);
-}
-
-static int asl_log_from_descriptor(aslclient ac, aslmsg am, int level, int descriptor) {
- int err __block = 0;
- static dispatch_once_t once_control;
- dispatch_once_f(&once_control, NULL, asl_descriptor_init);
- asl_client_t *asl = (asl_client_t *)ac;
- asl_msg_t *msg = (asl_msg_t *)am;
-
- if (descriptor < 0)
- return EBADF;
-
- if (msg != NULL) {
- msg = asl_msg_copy(msg);
- if (msg == NULL)
- return ENOMEM;
- }
-
- dispatch_sync(redirect_serial_q, ^{
- dispatch_source_t read_source;
-
- /* Reallocate if we need more space */
- if (descriptor >= n_redirect_descriptors) {
- size_t new_n = 1 << (fls(descriptor) + 1);
- asl_redirect_t *new_array = realloc(redirect_descriptors, new_n * sizeof(*redirect_descriptors));
- if (!new_array) {
- err = errno;
- return;
- }
- redirect_descriptors = new_array;
- memset(redirect_descriptors + n_redirect_descriptors, 0, (new_n - n_redirect_descriptors) * sizeof(*redirect_descriptors));
- n_redirect_descriptors = new_n;
- }
-
- /* If we're already listening on it, return error. */
- if (redirect_descriptors[descriptor].buf != NULL) {
- err = EBADF;
- return;
- }
-
- /* Initialize our buffer */
- redirect_descriptors[descriptor].buf = (char *)malloc(BUF_SIZE);
- if (redirect_descriptors[descriptor].buf == NULL) {
- err = errno;
- return;
- }
- redirect_descriptors[descriptor].w = redirect_descriptors[descriptor].buf;
-
- /* Store our ASL settings */
- redirect_descriptors[descriptor].level = level;
- redirect_descriptors[descriptor].asl = asl_client_retain(asl);
- redirect_descriptors[descriptor].msg = msg;
-
- /* Don't block on reads from this descriptor */
- (void)fcntl(descriptor, F_SETFL, O_NONBLOCK);
-
- /* Start listening */
- read_source = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, descriptor, 0, redirect_serial_q);
- redirect_descriptors[descriptor].read_source = read_source;
- dispatch_set_context(read_source, read_source);
- dispatch_source_set_event_handler_f(read_source, read_from_source);
- dispatch_source_set_cancel_handler_f(read_source, cancel_source);
- dispatch_group_enter(read_source_group);
- dispatch_resume(read_source);
- });
-
- if (err) {
- asl_msg_release(msg);
- }
-
- return err;
-}
-
-int asl_log_descriptor(aslclient ac, aslmsg am, int level, int descriptor, uint32_t fd_type) {
- int pipepair[2];
- int retval;
- int oerrno = errno;
-
- if (fd_type == ASL_LOG_DESCRIPTOR_READ)
- return asl_log_from_descriptor(ac, am, level, descriptor);
-
- assert(fd_type == ASL_LOG_DESCRIPTOR_WRITE);
-
- /* Create pipe */
- if (pipe(pipepair) == -1) {
- retval = errno;
- errno = oerrno;
- return retval;
- }
-
- /* Close the read descriptor but not the write descriptor on exec */
- if (fcntl(pipepair[0], F_SETFD, FD_CLOEXEC) == -1) {
- retval = errno;
- errno = oerrno;
- return retval;
- }
-
- /* Replace the existing descriptor */
- if (dup2(pipepair[1], descriptor) == -1) {
- close(pipepair[0]);
- close(pipepair[1]);
- retval = errno;
- errno = oerrno;
- return retval;
- }
-
- /* If we capture STDOUT_FILENO, make sure we linebuffer stdout */
- if (descriptor == STDOUT_FILENO)
- setlinebuf(stdout);
-
- /* Close the duplicate descriptors since they've been reassigned */
- close(pipepair[1]);
-
- /* Hand off the read end of our pipe to asl_log_descriptor */
- return asl_log_from_descriptor(ac, am, level, pipepair[0]);
-}
projects / apple / libc.git / blobdiff