Add poll/epoll compat layer for session daemon

[lttng-tools.git] / include / lttng-share.h

diff --git a/include/lttng-share.h b/include/lttng-share.h
index f61e24dbbb05c9f145ee1a14cab585e8900b755d..4e079d241f5392d05aee65acdfe5ca3375fd0b07 100644 (file)
--- a/include/lttng-share.h
+++ b/include/lttng-share.h
@@ -3,8 +3,8 @@
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
+ * as published by the Free Software Foundation; only version 2
+ * of the License.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -19,11 +19,54 @@
 #ifndef _LTTNG_SHARE_H
 #define _LTTNG_SHARE_H
 
-#include <stdint.h>
+/* Default channel attributes */
+#define DEFAULT_CHANNEL_NAME            "channel0"
+#define DEFAULT_CHANNEL_OVERWRITE       0       /* usec */
+/* DEFAULT_CHANNEL_SUBBUF_SIZE must always be a power of 2 */
+#define DEFAULT_CHANNEL_SUBBUF_SIZE     4096    /* bytes */
+/* DEFAULT_CHANNEL_SUBBUF_NUM must always be a power of 2 */
+#define DEFAULT_CHANNEL_SUBBUF_NUM      8
+#define DEFAULT_CHANNEL_SWITCH_TIMER    0       /* usec */
+#define DEFAULT_CHANNEL_READ_TIMER             200     /* usec */
+#define DEFAULT_CHANNEL_OUTPUT          LTTNG_EVENT_MMAP
 
-typedef uint32_t u32;
-typedef uint64_t u64;
+#define DEFAULT_METADATA_SUBBUF_SIZE    4096
+#define DEFAULT_METADATA_SUBBUF_NUM     2
 
-#define LTTNG_RUNDIR        "/var/run/lttng"
+/* Kernel has different defaults */
+
+/* DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE must always be a power of 2 */
+#define DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE  262144    /* bytes */
+/* DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM must always be a power of 2 */
+#define DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM   4
+/* See lttng-kernel.h enum lttng_kernel_output for channel output */
+#define DEFAULT_KERNEL_CHANNEL_OUTPUT       LTTNG_EVENT_SPLICE
+
+/*
+ * Takes a pointer x and transform it so we can use it to access members
+ * without a function call. Here an example:
+ *
+ *    #define GET_SIZE(x) LTTNG_REF(x)->size
+ *
+ *    struct { int size; } s;
+ *
+ *    printf("size : %d\n", GET_SIZE(&s));
+ *
+ * For this example we can't use something like this for compatibility purpose
+ * since this will fail:
+ *
+ *    #define GET_SIZE(x) x->size;
+ *
+ * This is mostly use for the compatibility layer of lttng-tools. See
+ * poll/epoll for a good real example. Since x can be on the stack or allocated
+ * memory using malloc(), we must use generic accessors for compat in order to
+ * *not* use a function to access members.
+ */
+#define LTTNG_REF(x) ((typeof(*x) *)(x))
+
+/*
+ * Memory allocation zeroed
+ */
+#define zmalloc(x) calloc(1, x)
 
 #endif /* _LTTNG_SHARE_H */