1 files changed, 229 insertions, 0 deletions
diff --git a/launchd/console_redirect.c b/launchd/console_redirect.c
new file mode 100644
index 0000000..dda84f1
--- /dev/null
+++ b/launchd/console_redirect.c
@@ -0,0 +1,229 @@
+/* Copyright (c) 2011 Apple Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT.  IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT
+ * HOLDER(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name(s) of the above
+ * copyright holders shall not be used in advertising or otherwise to
+ * promote the sale, use or other dealings in this Software without
+ * prior written authorization.
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/event.h>
+#include <asl.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+
+#define BUF_SIZE 1024
+
+typedef struct {
+    /* Initialized values */
+    int fd;
+    int level;
+    aslclient aslc;
+    aslmsg aslm;
+
+    /* Buffer for reading */
+    char buf[BUF_SIZE];
+    char *w;
+    int closed;
+} asl_redirect;
+
+/* Redirect stdout/stderr to asl */
+static void *redirect_thread(void *ctx) {
+    asl_redirect *fds = ctx;
+    char *p, *s;
+    ssize_t nbytes;
+    struct kevent ev[2];
+    int kq, n;
+
+    /* Setup our kqueue */
+    kq = kqueue();
+    EV_SET(&ev[0], fds[0].fd, EVFILT_READ, EV_ADD, 0, 0, 0);
+    EV_SET(&ev[1], fds[1].fd, EVFILT_READ, EV_ADD, 0, 0, 0);
+    n = kevent(kq, ev, 2, NULL, 0, NULL);
+
+    /* Set our buffers to empty */
+    fds[0].w = fds[0].buf;
+    fds[1].w = fds[1].buf;
+
+    /* Start off open */
+    fds[0].closed = fds[1].closed = 0;
+
+    while(!(fds[0].closed && fds[1].closed)) {
+        n = kevent(kq, NULL, 0, ev, 1, NULL);
+        if(n < 0) {
+            asl_log(fds[1].aslc, fds[1].aslm, ASL_LEVEL_ERR, "read failure: %s", strerror(errno));
+            break;
+        }
+
+        if(n == 1 && ev->filter == EVFILT_READ) {
+            int fd = ev->ident;
+            asl_redirect *aslr;
+
+            if(fd == fds[0].fd) {
+                aslr = &fds[0];
+            } else if(fd == fds[1].fd) {
+                aslr = &fds[1];
+            } else {
+                asl_log(fds[1].aslc, fds[1].aslm, ASL_LEVEL_ERR, "unexpected file descriptor: %d", fd);
+                break;
+            }
+
+            if(ev->flags & EV_EOF) {
+                EV_SET(&ev[1], aslr->fd, EVFILT_READ, EV_DELETE, 0, 0, 0);
+                kevent(kq, &ev[1], 1, NULL, 0, NULL);
+                close(aslr->fd);
+                aslr->closed = 1;
+                continue;
+            }
+
+            nbytes = read(fd, aslr->w, BUF_SIZE - (aslr->w - aslr->buf) - 1);
+            if(nbytes > 0) {
+                nbytes += (aslr->w - aslr->buf);
+                aslr->buf[nbytes] = '\0';
+
+                /* One line at a time */
+                for(p=aslr->buf; *p && (p - aslr->buf) < nbytes; p = s + 1) {
+                    // Find null or \n
+                    for(s=p; *s && *s != '\n'; s++);
+                    if(*s == '\n') {
+                        *s='\0';
+                        asl_log(aslr->aslc, aslr->aslm, aslr->level, "%s", p);
+                    } else if(aslr->buf != p) {
+                        memmove(aslr->buf, p, BUF_SIZE);
+                        aslr->w = aslr->buf + (s - p);
+                        break;
+                    } else if(nbytes == BUF_SIZE - 1) {
+                        asl_log(aslr->aslc, aslr->aslm, aslr->level, "%s", p);
+                        aslr->w = aslr->buf;
+                        break;
+                    }
+                }
+            }
+        }
+    }
+
+    return NULL;
+}
+
+static pthread_t redirect_pthread;
+static void redirect_atexit(void) {
+    /* stdout is linebuffered, so flush the buffer */
+    fflush(stdout);
+
+    /* close our pipes, causing the redirect thread to terminate */
+    close(STDOUT_FILENO);
+    close(STDERR_FILENO);
+    pthread_join(redirect_pthread, NULL);
+}
+
+int console_redirect(aslclient aslc, aslmsg aslm, int stdout_level, int stderr_level) {
+    int err;
+    int outpair[2];
+    int errpair[2];
+    static asl_redirect readpair[2];
+
+    /* Create pipes */
+    if(pipe(outpair) == -1) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "pipe() failed: %s", strerror(errno));
+        return errno;
+    }
+
+    if(pipe(errpair) == -1) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "pipe() failed: %s", strerror(errno));
+        close(outpair[0]);
+        close(outpair[1]);
+        return errno;
+    }
+
+    /* Close the read fd but not the write fd on exec */
+    fcntl(outpair[0], F_SETFD, FD_CLOEXEC);
+    fcntl(errpair[0], F_SETFD, FD_CLOEXEC);
+
+    /* Setup the context to handoff to the read thread */
+    readpair[0].fd = outpair[0];
+    readpair[0].level = stdout_level;
+    readpair[0].aslc = aslc;
+    readpair[0].aslm = aslm;
+
+    readpair[1].fd = errpair[0];
+    readpair[1].level = stderr_level;
+    readpair[1].aslc = aslc;
+    readpair[1].aslm = aslm;
+
+    /* Handoff to the read thread */
+    if((err = pthread_create(&redirect_pthread, NULL, redirect_thread, readpair)) != 0) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "pthread_create() failed: %s", strerror(err));
+        close(outpair[0]);
+        close(outpair[1]);
+        close(errpair[0]);
+        close(errpair[1]);
+        return err;
+    }
+
+    /* Replace our stdout fd.  force stdout to be line buffered since it defaults to buffered when not a tty */
+    if(dup2(outpair[1], STDOUT_FILENO) == -1) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "dup2(stdout) failed: %s", strerror(errno));
+    } else if(setlinebuf(stdout) != 0) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "setlinebuf(stdout) failed, log redirection may be delayed.");
+    }
+
+    /* Replace our stderr fd.  stderr is always unbuffered */
+    if(dup2(errpair[1], STDERR_FILENO) == -1) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "dup2(stderr) failed: %s", strerror(errno));
+    }
+
+    /* Close the duplicate fds since they've been reassigned */
+    close(outpair[1]);
+    close(errpair[1]);
+
+    /* Register an atexit handler to wait for the logs to flush */
+    if(atexit(redirect_atexit) != 0) {
+        asl_log(aslc, aslm, ASL_LEVEL_ERR, "atexit(redirect_atexit) failed: %s", strerror(errno));
+    }
+
+    return 0;
+}
+
+#ifdef DEBUG_CONSOLE_REDIRECT
+int main(int argc, char **argv) {
+    console_redirect(NULL, NULL, ASL_LEVEL_NOTICE, ASL_LEVEL_ERR);
+
+    fprintf(stderr, "TEST ERR1\n");
+    fprintf(stdout, "TEST OUT1\n");
+    fprintf(stderr, "TEST ERR2\n");
+    fprintf(stdout, "TEST OUT2\n");
+    system("/bin/echo SYST OUT");
+    system("/bin/echo SYST ERR >&2");
+    fprintf(stdout, "TEST OUT3\n");
+    fprintf(stdout, "TEST OUT4\n");
+    fprintf(stderr, "TEST ERR3\n");
+    fprintf(stderr, "TEST ERR4\n");
+
+    exit(0);
+}
+#endif