| 1 | #ifndef _BABELTRACE_CONTEXT_H |
| 2 | #define _BABELTRACE_CONTEXT_H |
| 3 | |
| 4 | /* |
| 5 | * BabelTrace |
| 6 | * |
| 7 | * context header |
| 8 | * |
| 9 | * Copyright 2012 EfficiOS Inc. and Linux Foundation |
| 10 | * |
| 11 | * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 12 | * Julien Desfossez <julien.desfossez@efficios.com> |
| 13 | * |
| 14 | * Permission is hereby granted, free of charge, to any person obtaining |
| 15 | * a copy of this software and associated documentation files (the |
| 16 | * "Software"), to deal in the Software without restriction, including |
| 17 | * without limitation the rights to use, copy, modify, merge, publish, |
| 18 | * distribute, sublicense, and/or sell copies of the Software, and to |
| 19 | * permit persons to whom the Software is furnished to do so, subject to |
| 20 | * the following conditions: |
| 21 | * |
| 22 | * The above copyright notice and this permission notice shall be |
| 23 | * included in all copies or substantial portions of the Software. |
| 24 | * |
| 25 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 26 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 27 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 28 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 29 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 30 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 31 | * SOFTWARE. |
| 32 | */ |
| 33 | |
| 34 | #include <unistd.h> |
| 35 | #include <babeltrace/format.h> |
| 36 | |
| 37 | #ifdef __cplusplus |
| 38 | extern "C" { |
| 39 | #endif |
| 40 | |
| 41 | /* struct bt_context is opaque to the user */ |
| 42 | struct bt_context; |
| 43 | struct bt_stream_pos; |
| 44 | struct bt_ctf_event; |
| 45 | |
| 46 | /* |
| 47 | * bt_context_create : create a Babeltrace context |
| 48 | * |
| 49 | * Allocate a new context. The creation of the context sets the refcount |
| 50 | * to 1. |
| 51 | * |
| 52 | * Returns an allocated context on success and NULL on error |
| 53 | */ |
| 54 | struct bt_context *bt_context_create(void); |
| 55 | |
| 56 | /* |
| 57 | * bt_context_add_trace : Add a trace by path to the context |
| 58 | * |
| 59 | * Open a trace. |
| 60 | * |
| 61 | * path is the path to the trace, it is not recursive. If "path" is NULL, |
| 62 | * stream_list is used instead as a list of mmap streams to open for the trace. |
| 63 | * |
| 64 | * format is a string containing the format name in which the trace was |
| 65 | * produced. |
| 66 | * |
| 67 | * packet_seek can be NULL to use the default packet_seek handler provided by |
| 68 | * the trace format. If non-NULL, it is used as an override of the handler for |
| 69 | * seeks across packets. It takes as parameter a stream position, the packet |
| 70 | * index it needs to seek to (for SEEK_SET), and a "whence" parameter (either |
| 71 | * SEEK_CUR: seek to next packet, or SEEK_SET: seek to packet at packet index). |
| 72 | * |
| 73 | * stream_list is a linked list of streams, it is used to open a trace where |
| 74 | * the trace data is located in memory mapped areas instead of trace files, |
| 75 | * this argument should be non-NULL when path is NULL. |
| 76 | * |
| 77 | * The metadata parameter acts as a metadata override when not NULL, otherwise |
| 78 | * the format handles the metadata opening. |
| 79 | * |
| 80 | * Return: the trace handle id (>= 0) on success, a negative |
| 81 | * value on error. |
| 82 | */ |
| 83 | int bt_context_add_trace(struct bt_context *ctx, const char *path, |
| 84 | const char *format, |
| 85 | void (*packet_seek)(struct bt_stream_pos *pos, |
| 86 | size_t index, int whence), |
| 87 | struct bt_mmap_stream_list *stream_list, |
| 88 | FILE *metadata); |
| 89 | |
| 90 | /* |
| 91 | * bt_context_remove_trace: Remove a trace from the context. |
| 92 | * |
| 93 | * Effectively closing the trace. Return negative error value if trace |
| 94 | * is not in context. |
| 95 | */ |
| 96 | int bt_context_remove_trace(struct bt_context *ctx, int trace_id); |
| 97 | |
| 98 | /* |
| 99 | * bt_context_get and bt_context_put : increments and decrement the |
| 100 | * refcount of the context |
| 101 | * |
| 102 | * These functions ensures that the context won't be destroyed when it |
| 103 | * is in use. The same number of get and put (plus one extra put to |
| 104 | * release the initial reference done at creation) has to be done to |
| 105 | * destroy a context. |
| 106 | * |
| 107 | * When the context refcount is decremented to 0 by a bt_context_put, |
| 108 | * the context is freed. |
| 109 | */ |
| 110 | void bt_context_get(struct bt_context *ctx); |
| 111 | void bt_context_put(struct bt_context *ctx); |
| 112 | |
| 113 | /* |
| 114 | * bt_ctf_get_context : get the context associated with an event |
| 115 | * |
| 116 | * Returns NULL on error |
| 117 | */ |
| 118 | struct bt_context *bt_ctf_event_get_context(const struct bt_ctf_event *event); |
| 119 | |
| 120 | #ifdef __cplusplus |
| 121 | } |
| 122 | #endif |
| 123 | |
| 124 | #endif /* _BABELTRACE_CONTEXT_H */ |