--- /dev/null
+/*
+ * Copyright (C) 2020 Philippe Proulx <pproulx@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#ifndef LTTNG_EVENT_EXPR_H
+#define LTTNG_EVENT_EXPR_H
+
+#include <stdbool.h>
+
+struct lttng_event_expr;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Types of an event expression.
+ */
+enum lttng_event_expr_type {
+ /*
+ * Returned by lttng_event_expr_get_type() with an invalid
+ * parameter.
+ */
+ LTTNG_EVENT_EXPR_TYPE_INVALID = -1,
+
+ /*
+ * The named payload field of an event.
+ *
+ * Command-line expression example:
+ *
+ * next_prio
+ */
+ LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD = 0,
+
+ /*
+ * The named per-channel context field of an event.
+ *
+ * Command-line expression example:
+ *
+ * $ctx.vpid
+ */
+ LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD = 1,
+
+ /*
+ * The named application-specific context field of an event.
+ *
+ * Command-line expression example:
+ *
+ * $app.iga:active-clients
+ */
+ LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD = 2,
+
+ /*
+ * The element of an array field.
+ *
+ * Command-line expression example:
+ *
+ * my_field[4]
+ * $ctx.some_context[5][1]
+ */
+ LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT = 3,
+};
+
+/*
+ * Event expression API status codes.
+ */
+enum lttng_event_expr_status {
+ /*
+ * Invalid parameter.
+ */
+ LTTNG_EVENT_EXPR_STATUS_INVALID = -1,
+
+ /*
+ * Success.
+ */
+ LTTNG_EVENT_EXPR_STATUS_OK = 0,
+};
+
+/*
+ * Returns the type of the event expression `expr`, or
+ * `LTTNG_EVENT_EXPR_TYPE_INVALID` if `expr` is `NULL`.
+ */
+extern enum lttng_event_expr_type lttng_event_expr_get_type(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Creates an event payload field expression for the payload field named
+ * `field_name`.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ * * `field_name` is `NULL`.
+ */
+extern struct lttng_event_expr *lttng_event_expr_event_payload_field_create(
+ const char *field_name);
+
+/*
+ * Returns the field name of the event payload field expression `expr`,
+ * or `NULL` if:
+ *
+ * * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD`.
+ */
+extern const char *lttng_event_expr_event_payload_field_get_name(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Creates a per-channel context field expression for the per-channel
+ * context field named `field_name`.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ * * `field_name` is `NULL`.
+ */
+extern struct lttng_event_expr *
+lttng_event_expr_channel_context_field_create(const char *field_name);
+
+/*
+ * Returns the field name of the per-channel context field
+ * expression `expr`, or `NULL` if:
+ *
+ * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD`.
+ */
+extern const char *lttng_event_expr_channel_context_field_get_name(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Creates an application-specific context field expression for the
+ * application-specific context field provided by the provider named
+ * `provider_name` and having the type named `type_name`.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ * * `provider_name` is `NULL`.
+ * * `type_name` is `NULL`.
+ */
+extern struct lttng_event_expr *
+lttng_event_expr_app_specific_context_field_create(
+ const char *provider_name, const char *type_name);
+
+/*
+ * Returns the provider name of the application-specific context field
+ * expression `expr`, or `NULL` if:
+ *
+ * * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD`.
+ */
+extern const char *
+lttng_event_expr_app_specific_context_field_get_provider_name(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Returns the type name of the application-specific context field
+ * expression `expr`, or `NULL` if:
+ *
+ * * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD`.
+ */
+extern const char *
+lttng_event_expr_app_specific_context_field_get_type_name(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Creates an array field element expression for the parent array field
+ * `array_field_expr` (transfering the ownership) and the index `index`.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ * * `array_field_expr` is `NULL`.
+ * * `array_field_expr` is not a locator expression, that is, its type
+ * is not one of:
+ *
+ * * `LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD`
+ * * `LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD`
+ * * `LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD`
+ * * `LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT`
+ */
+extern struct lttng_event_expr *lttng_event_expr_array_field_element_create(
+ struct lttng_event_expr *array_field_expr,
+ unsigned int index);
+
+/*
+ * Returns the parent array field expression of the array field element
+ * expression `expr`, or `NULL` if:
+ *
+ * * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT`.
+ */
+extern const struct lttng_event_expr *
+lttng_event_expr_array_field_element_get_parent_expr(
+ const struct lttng_event_expr *expr);
+
+/*
+ * Sets `*index` to the index of the array field element expression
+ * `expr`.
+ *
+ * Returns:
+ *
+ * `LTTNG_EVENT_EXPR_STATUS_OK`:
+ * Success.
+ *
+ * `LTTNG_EVENT_EXPR_STATUS_INVALID`:
+ * * `expr` is `NULL`.
+ * * The type of `expr` is not
+ * `LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT`.
+ * * `index` is `NULL`.
+ */
+extern enum lttng_event_expr_status
+lttng_event_expr_array_field_element_get_index(
+ const struct lttng_event_expr *expr, unsigned int *index);
+
+/*
+ * Returns whether or not the event expressions `expr_a` and `expr_b`
+ * are equal.
+ *
+ * `expr_a` and `expr_b` can be `NULL`.
+ */
+extern bool lttng_event_expr_is_equal(const struct lttng_event_expr *expr_a,
+ const struct lttng_event_expr *expr_b);
+
+/*
+ * Destroys the event expression `expr` if not `NULL`.
+ */
+extern void lttng_event_expr_destroy(struct lttng_event_expr *expr);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LTTNG_EVENT_EXPR_H */
--- /dev/null
+/*
+ * event-expr.c
+ *
+ * Linux Trace Toolkit Control Library
+ *
+ * Copyright (C) 2020 Philippe Proulx <pproulx@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#define _LGPL_SOURCE
+#include <assert.h>
+#include <stddef.h>
+
+#include <common/error.h>
+#include <common/macros.h>
+#include <lttng/event-expr-internal.h>
+
+enum lttng_event_expr_type lttng_event_expr_get_type(
+ const struct lttng_event_expr *expr)
+{
+ enum lttng_event_expr_type type;
+
+ if (!expr) {
+ type = LTTNG_EVENT_EXPR_TYPE_INVALID;
+ goto end;
+ }
+
+ type = expr->type;
+
+end:
+ return type;
+}
+
+static
+struct lttng_event_expr *create_empty_expr(enum lttng_event_expr_type type,
+ size_t size)
+{
+ struct lttng_event_expr *expr;
+
+ expr = zmalloc(size);
+ if (!expr) {
+ goto end;
+ }
+
+ expr->type = type;
+
+end:
+ return expr;
+}
+
+static
+struct lttng_event_expr_field *create_field_event_expr(
+ enum lttng_event_expr_type type,
+ const char *name)
+{
+ struct lttng_event_expr_field *expr =
+ container_of(
+ create_empty_expr(type, sizeof(*expr)),
+ struct lttng_event_expr_field, parent);
+
+ if (!expr) {
+ goto error;
+ }
+
+ assert(name);
+ expr->name = strdup(name);
+ if (!expr->name) {
+ goto error;
+ }
+
+ goto end;
+
+error:
+ lttng_event_expr_destroy(&expr->parent);
+
+end:
+ return expr;
+}
+
+struct lttng_event_expr *lttng_event_expr_event_payload_field_create(
+ const char *field_name)
+{
+ struct lttng_event_expr *expr = NULL;
+
+ if (!field_name) {
+ goto end;
+ }
+
+ expr = &create_field_event_expr(
+ LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD,
+ field_name)->parent;
+
+end:
+ return expr;
+}
+
+struct lttng_event_expr *lttng_event_expr_channel_context_field_create(
+ const char *field_name)
+{
+ struct lttng_event_expr *expr = NULL;
+
+ if (!field_name) {
+ goto end;
+ }
+
+ expr = &create_field_event_expr(
+ LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD,
+ field_name)->parent;
+
+end:
+ return expr;
+}
+
+struct lttng_event_expr *lttng_event_expr_app_specific_context_field_create(
+ const char *provider_name, const char *type_name)
+{
+ struct lttng_event_expr_app_specific_context_field *expr = NULL;
+
+ if (!type_name || !provider_name) {
+ goto error;
+ }
+
+ expr = container_of(create_empty_expr(
+ LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD,
+ sizeof(*expr)),
+ struct lttng_event_expr_app_specific_context_field,
+ parent);
+ if (!expr) {
+ goto error;
+ }
+
+ expr->provider_name = strdup(provider_name);
+ if (!expr->provider_name) {
+ goto error;
+ }
+
+ expr->type_name = strdup(type_name);
+ if (!expr->type_name) {
+ goto error;
+ }
+
+ goto end;
+
+error:
+ lttng_event_expr_destroy(&expr->parent);
+
+end:
+ return &expr->parent;
+}
+
+struct lttng_event_expr *lttng_event_expr_array_field_element_create(
+ struct lttng_event_expr *array_field_expr,
+ unsigned int index)
+{
+ struct lttng_event_expr_array_field_element *expr = NULL;
+
+ /* The parent array field expression must be an l-value */
+ if (!array_field_expr ||
+ !lttng_event_expr_is_lvalue(array_field_expr)) {
+ goto error;
+ }
+
+ expr = container_of(create_empty_expr(
+ LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT,
+ sizeof(*expr)),
+ struct lttng_event_expr_array_field_element,
+ parent);
+ if (!expr) {
+ goto error;
+ }
+
+ expr->array_field_expr = array_field_expr;
+ expr->index = index;
+ goto end;
+
+error:
+ lttng_event_expr_destroy(&expr->parent);
+
+end:
+ return &expr->parent;
+}
+
+const char *lttng_event_expr_event_payload_field_get_name(
+ const struct lttng_event_expr *expr)
+{
+ const char *ret = NULL;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD) {
+ goto end;
+ }
+
+ ret = container_of(expr,
+ const struct lttng_event_expr_field, parent)->name;
+
+end:
+ return ret;
+}
+
+const char *lttng_event_expr_channel_context_field_get_name(
+ const struct lttng_event_expr *expr)
+{
+ const char *ret = NULL;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD) {
+ goto end;
+ }
+
+ ret = container_of(expr,
+ const struct lttng_event_expr_field, parent)->name;
+
+end:
+ return ret;
+}
+
+const char *lttng_event_expr_app_specific_context_field_get_provider_name(
+ const struct lttng_event_expr *expr)
+{
+ const char *ret = NULL;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD) {
+ goto end;
+ }
+
+ ret = container_of(expr,
+ const struct lttng_event_expr_app_specific_context_field,
+ parent)->provider_name;
+
+end:
+ return ret;
+}
+
+const char *lttng_event_expr_app_specific_context_field_get_type_name(
+ const struct lttng_event_expr *expr)
+{
+ const char *ret = NULL;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD) {
+ goto end;
+ }
+
+ ret = container_of(expr,
+ const struct lttng_event_expr_app_specific_context_field,
+ parent)->type_name;
+
+end:
+ return ret;
+}
+
+const struct lttng_event_expr *
+lttng_event_expr_array_field_element_get_parent_expr(
+ const struct lttng_event_expr *expr)
+{
+ const struct lttng_event_expr *ret = NULL;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT) {
+ goto end;
+ }
+
+ ret = container_of(expr,
+ const struct lttng_event_expr_array_field_element,
+ parent)->array_field_expr;
+
+end:
+ return ret;
+}
+
+enum lttng_event_expr_status lttng_event_expr_array_field_element_get_index(
+ const struct lttng_event_expr *expr, unsigned int *index)
+{
+ enum lttng_event_expr_status ret = LTTNG_EVENT_EXPR_STATUS_OK;
+
+ if (!expr || expr->type != LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT ||
+ !index) {
+ ret = LTTNG_EVENT_EXPR_STATUS_INVALID;
+ goto end;
+ }
+
+ *index = container_of(expr,
+ const struct lttng_event_expr_array_field_element,
+ parent)->index;
+
+end:
+ return ret;
+}
+
+bool lttng_event_expr_is_equal(const struct lttng_event_expr *expr_a,
+ const struct lttng_event_expr *expr_b)
+{
+ bool is_equal = true;
+
+ if (!expr_a && !expr_b) {
+ /* Both `NULL`: equal */
+ goto end;
+ }
+
+ if (!expr_a || !expr_b) {
+ /* Only one `NULL`: not equal */
+ goto not_equal;
+ }
+
+ if (expr_a->type != expr_b->type) {
+ /* Different types: not equal */
+ goto not_equal;
+ }
+
+ switch (expr_a->type) {
+ case LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD:
+ case LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD:
+ {
+ const struct lttng_event_expr_field *field_expr_a =
+ container_of(expr_a,
+ const struct lttng_event_expr_field,
+ parent);
+ const struct lttng_event_expr_field *field_expr_b =
+ container_of(expr_b,
+ const struct lttng_event_expr_field,
+ parent);
+
+ if (strcmp(field_expr_a->name, field_expr_b->name) != 0) {
+ goto not_equal;
+ }
+
+ break;
+ }
+ case LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD:
+ {
+ const struct lttng_event_expr_app_specific_context_field *field_expr_a =
+ container_of(expr_a,
+ const struct lttng_event_expr_app_specific_context_field,
+ parent);
+ const struct lttng_event_expr_app_specific_context_field *field_expr_b =
+ container_of(expr_b,
+ const struct lttng_event_expr_app_specific_context_field,
+ parent);
+
+ if (strcmp(field_expr_a->provider_name,
+ field_expr_b->provider_name) != 0) {
+ goto not_equal;
+ }
+
+ if (strcmp(field_expr_a->type_name,
+ field_expr_b->type_name) != 0) {
+ goto not_equal;
+ }
+
+ break;
+ }
+ case LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT:
+ {
+ const struct lttng_event_expr_array_field_element *elem_expr_a =
+ container_of(expr_a,
+ const struct lttng_event_expr_array_field_element,
+ parent);
+ const struct lttng_event_expr_array_field_element *elem_expr_b =
+ container_of(expr_b,
+ const struct lttng_event_expr_array_field_element,
+ parent);
+
+ if (!lttng_event_expr_is_equal(elem_expr_a->array_field_expr,
+ elem_expr_b->array_field_expr)) {
+ goto not_equal;
+ }
+
+ if (elem_expr_a->index != elem_expr_b->index) {
+ goto not_equal;
+ }
+
+ break;
+ }
+ default:
+ break;
+ }
+
+ goto end;
+
+not_equal:
+ is_equal = false;
+
+end:
+ return is_equal;
+}
+
+void lttng_event_expr_destroy(struct lttng_event_expr *expr)
+{
+ if (!expr) {
+ goto end;
+ }
+
+ switch (expr->type) {
+ case LTTNG_EVENT_EXPR_TYPE_EVENT_PAYLOAD_FIELD:
+ case LTTNG_EVENT_EXPR_TYPE_CHANNEL_CONTEXT_FIELD:
+ {
+ struct lttng_event_expr_field *field_expr =
+ container_of(expr,
+ struct lttng_event_expr_field, parent);
+
+ free(field_expr->name);
+ break;
+ }
+ case LTTNG_EVENT_EXPR_TYPE_APP_SPECIFIC_CONTEXT_FIELD:
+ {
+ struct lttng_event_expr_app_specific_context_field *field_expr =
+ container_of(expr,
+ struct lttng_event_expr_app_specific_context_field,
+ parent);
+
+ free(field_expr->provider_name);
+ free(field_expr->type_name);
+ break;
+ }
+ case LTTNG_EVENT_EXPR_TYPE_ARRAY_FIELD_ELEMENT:
+ {
+ struct lttng_event_expr_array_field_element *elem_expr =
+ container_of(expr,
+ struct lttng_event_expr_array_field_element,
+ parent);
+
+ lttng_event_expr_destroy(elem_expr->array_field_expr);
+ break;
+ }
+ default:
+ break;
+ }
+
+ free(expr);
+
+end:
+ return;
+}
projects / lttng-tools.git / commitdiff
