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Diffstat (limited to 'agent/tcf/system/pid-hash.h')
-rw-r--r--agent/tcf/system/pid-hash.h76
1 files changed, 76 insertions, 0 deletions
diff --git a/agent/tcf/system/pid-hash.h b/agent/tcf/system/pid-hash.h
new file mode 100644
index 00000000..4843ec8c
--- /dev/null
+++ b/agent/tcf/system/pid-hash.h
@@ -0,0 +1,76 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Wind River Systems, Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * and Eclipse Distribution License v1.0 which accompany this distribution.
+ * The Eclipse Public License is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * and the Eclipse Distribution License is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ * You may elect to redistribute this code under either of these licenses.
+ *
+ * Contributors:
+ * Wind River Systems - initial API and implementation
+ *******************************************************************************/
+
+/*
+ * This is utility module that contains context PID hash table implementation.
+ * System specific debug context code can use this module to implement context lookup.
+ */
+
+/* TODO: consider splitting the code into two files: some clients might want to reuse PID hash table for context_find_from_pid(),
+ * but use some other means to implement id2ctx() */
+
+#define CONTEXT_PID_HASH_SIZE (32 * MEM_USAGE_FACTOR - 1)
+#define CONTEXT_PID_HASH(PID) ((unsigned)(PID) % CONTEXT_PID_HASH_SIZE)
+
+static LINK context_pid_hash[CONTEXT_PID_HASH_SIZE];
+static size_t pid_hash_link_offset = 0;
+
+#define ctx2pidlink(ctx) ((LINK *)((char *)(ctx) + pid_hash_link_offset))
+#define pidlink2ctx(lnk) ((Context *)((char *)(lnk) - pid_hash_link_offset))
+
+static void link_context(Context * ctx) {
+ LINK * h = context_pid_hash + CONTEXT_PID_HASH(EXT(ctx)->pid);
+
+ assert(ctx->mem != NULL);
+ assert(EXT(ctx)->pid != 0);
+ assert(context_find_from_pid(EXT(ctx)->pid, ctx->parent != NULL) == NULL);
+ list_add_first(&ctx->ctxl, &context_root);
+ list_add_first(ctx2pidlink(ctx), h);
+ ctx->ref_count++;
+}
+
+Context * context_find_from_pid(pid_t pid, int thread) {
+ LINK * h = context_pid_hash + CONTEXT_PID_HASH(pid);
+ LINK * l = h->next;
+
+ assert(is_dispatch_thread());
+ if (l == NULL) return NULL;
+ while (l != h) {
+ Context * ctx = pidlink2ctx(l);
+ if (EXT(ctx)->pid == pid &&
+ (ctx->parent != NULL) == (thread != 0)) return ctx;
+ l = l->next;
+ }
+ return NULL;
+}
+
+Context * id2ctx(const char * id) {
+ pid_t parent = 0;
+ pid_t pid = id2pid(id, &parent);
+ if (pid == 0) return NULL;
+ return context_find_from_pid(pid, parent != 0);
+}
+
+static void pid_hash_context_exited(Context * ctx, void * args) {
+ list_remove(ctx2pidlink(ctx));
+}
+
+static void ini_context_pid_hash(void) {
+ int i;
+ static ContextEventListener l = { NULL, pid_hash_context_exited };
+ for (i = 0; i < CONTEXT_PID_HASH_SIZE; i++) list_init(context_pid_hash + i);
+ pid_hash_link_offset = context_extension(sizeof(LINK));
+ add_context_event_listener(&l, NULL);
+}

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