X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fpipe.c;h=c8f00141574c3a6f11ce278a4c4a07d9cad1fa46;hp=713db973972ab40de1b9414eebdf02b697545099;hb=9c2bd8db1c70269d37537b7d02bae41ccab29056;hpb=9fd926379bd4c6c17f2b3c39a5bbf9879bc74e14

diff --git a/src/common/pipe.c b/src/common/pipe.c
index 713db9739..c8f001415 100644
--- a/src/common/pipe.c
+++ b/src/common/pipe.c
@@ -15,10 +15,12 @@
  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 
 #include <common/common.h>
 
@@ -112,20 +114,69 @@ end:
 	return ret_val;
 }
 
+static struct lttng_pipe *_pipe_create(void)
+{
+	int ret;
+	struct lttng_pipe *p;
+
+	p = zmalloc(sizeof(*p));
+	if (!p) {
+		PERROR("zmalloc pipe create");
+		goto end;
+	}
+	p->fd[0] = p->fd[1] = -1;
+
+	ret = pthread_mutex_init(&p->read_mutex, NULL);
+	if (ret) {
+		PERROR("pthread_mutex_init read lock pipe create");
+		goto error_destroy;
+	}
+	ret = pthread_mutex_init(&p->write_mutex, NULL);
+	if (ret) {
+		PERROR("pthread_mutex_init write lock pipe create");
+		goto error_destroy_rmutex;
+	}
+end:
+	return p;
+error_destroy_rmutex:
+	(void) pthread_mutex_destroy(&p->read_mutex);
+error_destroy:
+	free(p);
+	return NULL;
+}
+
+static int _pipe_set_flags(struct lttng_pipe *pipe, int flags)
+{
+	int i, ret = 0;
+
+	if (!flags) {
+		goto end;
+	}
+
+	for (i = 0; i < 2; i++) {
+		ret = fcntl(pipe->fd[i], F_SETFD, flags);
+		if (ret < 0) {
+			PERROR("fcntl lttng pipe %d", flags);
+			goto end;
+		}
+	}
+end:
+	return ret;
+}
 
 /*
  * Open a new lttng pipe and set flags using fcntl().
  *
  * Return a newly allocated lttng pipe on success or else NULL.
  */
+LTTNG_HIDDEN
 struct lttng_pipe *lttng_pipe_open(int flags)
 {
 	int ret;
 	struct lttng_pipe *p;
 
-	p = zmalloc(sizeof(*p));
+	p = _pipe_create();
 	if (!p) {
-		PERROR("zmalloc pipe open");
 		goto error;
 	}
 
@@ -134,37 +185,81 @@ struct lttng_pipe *lttng_pipe_open(int flags)
 		PERROR("lttng pipe");
 		goto error;
 	}
+	p->r_state = LTTNG_PIPE_STATE_OPENED;
+	p->w_state = LTTNG_PIPE_STATE_OPENED;
 
-	if (flags) {
-		int i;
-
-		for (i = 0; i < 2; i++) {
-			ret = fcntl(p->fd[i], F_SETFD, flags);
-			if (ret < 0) {
-				PERROR("fcntl lttng pipe %d", flags);
-				goto error;
-			}
-		}
+	ret = _pipe_set_flags(p, flags);
+	if (ret) {
+		goto error;
 	}
 
-	pthread_mutex_init(&p->read_mutex, NULL);
-	pthread_mutex_init(&p->write_mutex, NULL);
-	p->r_state = LTTNG_PIPE_STATE_OPENED;
-	p->w_state = LTTNG_PIPE_STATE_OPENED;
 	p->flags = flags;
 
 	return p;
-
 error:
 	lttng_pipe_destroy(p);
 	return NULL;
 }
 
+/*
+ * Open a new lttng pipe at path and set flags using fcntl().
+ *
+ * Return a newly allocated lttng pipe on success or else NULL.
+ */
+LTTNG_HIDDEN
+struct lttng_pipe *lttng_pipe_named_open(const char *path, mode_t mode,
+		int flags)
+{
+	int ret, fd_r, fd_w;
+	struct lttng_pipe *pipe;
+
+	pipe = _pipe_create();
+	if (!pipe) {
+		goto error;
+	}
+
+	ret = mkfifo(path, mode);
+	if (ret) {
+		PERROR("mkfifo");
+		goto error;
+	}
+
+	fd_r = open(path, O_RDONLY | O_NONBLOCK);
+	if (fd_r < 0) {
+		PERROR("open fifo");
+		ret = fd_r;
+		goto error;
+	}
+	pipe->fd[0] = fd_r;
+	pipe->r_state = LTTNG_PIPE_STATE_OPENED;
+
+	fd_w = open(path, O_WRONLY | O_NONBLOCK);
+	if (fd_w < 0) {
+		PERROR("open fifo");
+		ret = fd_w;
+		goto error;
+	}
+	pipe->fd[1] = fd_w;
+	pipe->w_state = LTTNG_PIPE_STATE_OPENED;
+
+	ret = _pipe_set_flags(pipe, flags);
+	if (ret) {
+		goto error;
+	}
+	pipe->flags = flags;
+
+	return pipe;
+error:
+	lttng_pipe_destroy(pipe);
+	return NULL;
+}
+
 /*
  * Close read side of a lttng pipe.
  *
  * Return 0 on success else a negative value.
  */
+LTTNG_HIDDEN
 int lttng_pipe_read_close(struct lttng_pipe *pipe)
 {
 	int ret;
@@ -184,6 +279,7 @@ int lttng_pipe_read_close(struct lttng_pipe *pipe)
  *
  * Return 0 on success else a negative value.
  */
+LTTNG_HIDDEN
 int lttng_pipe_write_close(struct lttng_pipe *pipe)
 {
 	int ret;
@@ -202,6 +298,7 @@ int lttng_pipe_write_close(struct lttng_pipe *pipe)
  *
  * Return 0 on success else a negative value.
  */
+LTTNG_HIDDEN
 int lttng_pipe_close(struct lttng_pipe *pipe)
 {
 	int ret, ret_val = 0;
@@ -224,6 +321,7 @@ int lttng_pipe_close(struct lttng_pipe *pipe)
 /*
  * Close and destroy a lttng pipe object. Finally, pipe is freed.
  */
+LTTNG_HIDDEN
 void lttng_pipe_destroy(struct lttng_pipe *pipe)
 {
 	int ret;
@@ -257,51 +355,24 @@ void lttng_pipe_destroy(struct lttng_pipe *pipe)
 /*
  * Read on a lttng pipe and put the data in buf of at least size count.
  *
- * Return 0 on success or else a negative errno message from read(2).
+ * Return "count" on success. Return < count on error. errno can be used
+ * to check the actual error.
  */
+LTTNG_HIDDEN
 ssize_t lttng_pipe_read(struct lttng_pipe *pipe, void *buf, size_t count)
 {
-	ssize_t ret, read_len, read_left, index;
+	ssize_t ret;
 
 	assert(pipe);
 	assert(buf);
 
 	lock_read_side(pipe);
-
 	if (!lttng_pipe_is_read_open(pipe)) {
-		ret = -EBADF;
+		ret = -1;
+		errno = EBADF;
 		goto error;
 	}
-
-	read_left = count;
-	index = 0;
-	do {
-		read_len = read(pipe->fd[0], buf + index, read_left);
-		if (read_len < 0) {
-			ret = -errno;
-			if (errno == EINTR) {
-				/* Read again. */
-				continue;
-			} else if (errno == EAGAIN || errno == EWOULDBLOCK) {
-				/*
-				 * Return the number of bytes read up to this point if any.
-				 */
-				if (index) {
-					ret = index;
-				}
-				goto error;
-			} else {
-				PERROR("lttng pipe read");
-				goto error;
-			}
-		}
-		read_left -= read_len;
-		index += read_len;
-	} while (read_left > 0);
-
-	/* Everything went fine. */
-	ret = index;
-
+	ret = lttng_read(pipe->fd[0], buf, count);
 error:
 	unlock_read_side(pipe);
 	return ret;
@@ -310,52 +381,25 @@ error:
 /*
  * Write on a lttng pipe using the data in buf and size of count.
  *
- * Return 0 on success or else a negative errno message from write(2).
+ * Return "count" on success. Return < count on error. errno can be used
+ * to check the actual error.
  */
+LTTNG_HIDDEN
 ssize_t lttng_pipe_write(struct lttng_pipe *pipe, const void *buf,
 		size_t count)
 {
-	ssize_t ret, write_len, write_left, index;
+	ssize_t ret;
 
 	assert(pipe);
 	assert(buf);
 
 	lock_write_side(pipe);
-
 	if (!lttng_pipe_is_write_open(pipe)) {
-		ret = -EBADF;
+		ret = -1;
+		errno = EBADF;
 		goto error;
 	}
-
-	write_left = count;
-	index = 0;
-	do {
-		write_len = write(pipe->fd[1], buf + index, write_left);
-		if (write_len < 0) {
-			ret = -errno;
-			if (errno == EINTR) {
-				/* Read again. */
-				continue;
-			} else if (errno == EAGAIN || errno == EWOULDBLOCK) {
-				/*
-				 * Return the number of bytes read up to this point if any.
-				 */
-				if (index) {
-					ret = index;
-				}
-				goto error;
-			} else {
-				PERROR("lttng pipe write");
-				goto error;
-			}
-		}
-		write_left -= write_len;
-		index += write_len;
-	} while (write_left > 0);
-
-	/* Everything went fine. */
-	ret = index;
-
+	ret = lttng_write(pipe->fd[1], buf, count);
 error:
 	unlock_write_side(pipe);
 	return ret;