[ObjC capture] Model functions related to dispatch sources

Reviewed By: akotulski

Differential Revision: D4994125

fbshipit-source-id: 34ce0a8

infer/src/clang/cTrans_models.ml

@@ -214,6 +214,8 @@ let dispatch_functions = [
   ("dispatch_group_notify", 2);
   ("dispatch_group_wait", 2);
   ("dispatch_barrier_async", 1);
+  ("dispatch_source_set_cancel_handler", 1);
+  ("dispatch_source_set_event_handler", 1);
 ]
 
 let is_dispatch_function_name function_name =

infer/tests/codetoanalyze/objc/errors/Makefile

@@ -39,6 +39,7 @@ SOURCES_DEFAULT = \
   procdescs/MethodCall.m \
   property/main.c \
   resource_leaks/ResourceLeakExample.m \
+	resource_leaks/Dispatch_sources.m \
   shared/block/block-it.m \
   shared/block/dispatch.m \
   shared/category_procdesc/EOCPerson.m \

infer/tests/codetoanalyze/objc/errors/issues.exp

@@ -111,6 +111,7 @@ codetoanalyze/objc/errors/npe/block.m, BlockA_foo7, 2, IVAR_NOT_NULL_CHECKED, [s
 codetoanalyze/objc/errors/npe/ivar_blocks.m, MyClass_ivar_npe, 1, IVAR_NOT_NULL_CHECKED, [start of procedure ivar_npe]
 codetoanalyze/objc/errors/npe/skip_method_with_nil_object.m, SkipMethodNilA_testBug:, 6, PARAMETER_NOT_NULL_CHECKED, [start of procedure testBug:,Message get_a with receiver nil returns nil.,Message skip_method with receiver nil returns nil.,Condition is false]
 codetoanalyze/objc/errors/property/main.c, property_main, 3, MEMORY_LEAK, [start of procedure property_main(),Skipped call: function or method not found]
+codetoanalyze/objc/errors/resource_leaks/Dispatch_sources.m, __objc_anonymous_block_ProcessContentsOfFile______2, 6, MEMORY_LEAK, [start of procedure block,Skipped call: function or method not found,Condition is true,Skipped call: function or method not found]
 codetoanalyze/objc/errors/taint/sources.m, testNSHTTPCookie1, 5, TAINTED_VALUE_REACHING_SENSITIVE_FUNCTION, [start of procedure testNSHTTPCookie1()]
 codetoanalyze/objc/errors/taint/sources.m, testNSHTTPCookie2, 5, TAINTED_VALUE_REACHING_SENSITIVE_FUNCTION, [start of procedure testNSHTTPCookie2()]
 codetoanalyze/objc/errors/taint/sources.m, testNSHTTPCookie3, 5, TAINTED_VALUE_REACHING_SENSITIVE_FUNCTION, [start of procedure testNSHTTPCookie3()]

infer/tests/codetoanalyze/objc/errors/resource_leaks/Dispatch_sources.m

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2017 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+#import <Foundation/Foundation.h>
+
+Boolean MyProcessFileData(char* buffer, ssize_t actual);
+
+dispatch_source_t ProcessContentsOfFile(const char* filename) {
+  // Prepare the file for reading.
+  int fd = open("hi.txt", O_WRONLY | O_CREAT | O_TRUNC, 0600);
+  if (fd == -1)
+    return NULL;
+  fcntl(fd, F_SETFL, O_NONBLOCK); // Avoid blocking the read operation
+
+  dispatch_queue_t queue =
+      dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
+  dispatch_source_t readSource =
+      dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, fd, 0, queue);
+  if (!readSource) {
+    close(fd);
+    return NULL;
+  }
+
+  // Install the event handler
+  dispatch_source_set_event_handler(readSource, ^{
+    size_t estimated = dispatch_source_get_data(readSource) + 1;
+    // Read the data into a text buffer.
+    char* buffer = (char*)malloc(estimated);
+    if (buffer) {
+      ssize_t actual = read(fd, buffer, (estimated));
+      Boolean done = MyProcessFileData(buffer, actual); // Process the data.
+
+      // Release the buffer when done.
+      // free(buffer); // Don't release the buffer, report memory leak.
+
+      // If there is no more data, cancel the source.
+      if (done)
+        dispatch_source_cancel(readSource);
+    }
+  });
+
+  // Install the cancellation handler
+  dispatch_source_set_cancel_handler(readSource, ^{
+    close(fd);
+  });
+
+  // Start reading the file.
+  dispatch_resume(readSource);
+  return readSource;
+}