Clean up warnings in the malloc_debug_* files.

Also clean up cpplint.py-detected lint.

Change-Id: Ia18e89c4c6878764f8d7ed34b8247e7a8d8fe88b
diff --git a/libc/bionic/malloc_debug_common.cpp b/libc/bionic/malloc_debug_common.cpp
new file mode 100644
index 0000000..3a12cd4
--- /dev/null
+++ b/libc/bionic/malloc_debug_common.cpp
@@ -0,0 +1,527 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Contains definition of structures, global variables, and implementation of
+ * routines that are used by malloc leak detection code and other components in
+ * the system. The trick is that some components expect these data and
+ * routines to be defined / implemented in libc.so library, regardless
+ * whether or not MALLOC_LEAK_CHECK macro is defined. To make things even
+ * more tricky, malloc leak detection code, implemented in
+ * libc_malloc_debug.so also requires access to these variables and routines
+ * (to fill allocation entry hash table, for example). So, all relevant
+ * variables and routines are defined / implemented here and exported
+ * to all, leak detection code and other components via dynamic (libc.so),
+ * or static (libc.a) linking.
+ */
+
+#include <stdlib.h>
+#include <pthread.h>
+#include <unistd.h>
+#include "dlmalloc.h"
+#include "malloc_debug_common.h"
+
+/*
+ * In a VM process, this is set to 1 after fork()ing out of zygote.
+ */
+int gMallocLeakZygoteChild = 0;
+
+pthread_mutex_t gAllocationsMutex = PTHREAD_MUTEX_INITIALIZER;
+HashTable gHashTable;
+
+// =============================================================================
+// output functions
+// =============================================================================
+
+static int hash_entry_compare(const void* arg1, const void* arg2) {
+    int result;
+
+    const HashEntry* e1 = *static_cast<HashEntry* const*>(arg1);
+    const HashEntry* e2 = *static_cast<HashEntry* const*>(arg2);
+
+    // if one or both arg pointers are null, deal gracefully
+    if (e1 == NULL) {
+        result = (e2 == NULL) ? 0 : 1;
+    } else if (e2 == NULL) {
+        result = -1;
+    } else {
+        size_t nbAlloc1 = e1->allocations;
+        size_t nbAlloc2 = e2->allocations;
+        size_t size1 = e1->size & ~SIZE_FLAG_MASK;
+        size_t size2 = e2->size & ~SIZE_FLAG_MASK;
+        size_t alloc1 = nbAlloc1 * size1;
+        size_t alloc2 = nbAlloc2 * size2;
+
+        // sort in descending order by:
+        // 1) total size
+        // 2) number of allocations
+        //
+        // This is used for sorting, not determination of equality, so we don't
+        // need to compare the bit flags.
+        if (alloc1 > alloc2) {
+            result = -1;
+        } else if (alloc1 < alloc2) {
+            result = 1;
+        } else {
+            if (nbAlloc1 > nbAlloc2) {
+                result = -1;
+            } else if (nbAlloc1 < nbAlloc2) {
+                result = 1;
+            } else {
+                result = 0;
+            }
+        }
+    }
+    return result;
+}
+
+/*
+ * Retrieve native heap information.
+ *
+ * "*info" is set to a buffer we allocate
+ * "*overallSize" is set to the size of the "info" buffer
+ * "*infoSize" is set to the size of a single entry
+ * "*totalMemory" is set to the sum of all allocations we're tracking; does
+ *   not include heap overhead
+ * "*backtraceSize" is set to the maximum number of entries in the back trace
+ */
+extern "C" void get_malloc_leak_info(uint8_t** info, size_t* overallSize,
+        size_t* infoSize, size_t* totalMemory, size_t* backtraceSize) {
+    // don't do anything if we have invalid arguments
+    if (info == NULL || overallSize == NULL || infoSize == NULL ||
+            totalMemory == NULL || backtraceSize == NULL) {
+        return;
+    }
+    *totalMemory = 0;
+
+    ScopedPthreadMutexLocker locker(&gAllocationsMutex);
+
+    if (gHashTable.count == 0) {
+        *info = NULL;
+        *overallSize = 0;
+        *infoSize = 0;
+        *backtraceSize = 0;
+        return;
+    }
+
+    HashEntry** list = static_cast<HashEntry**>(dlmalloc(sizeof(void*) * gHashTable.count));
+
+    // get the entries into an array to be sorted
+    int index = 0;
+    for (size_t i = 0 ; i < HASHTABLE_SIZE ; ++i) {
+        HashEntry* entry = gHashTable.slots[i];
+        while (entry != NULL) {
+            list[index] = entry;
+            *totalMemory = *totalMemory +
+                ((entry->size & ~SIZE_FLAG_MASK) * entry->allocations);
+            index++;
+            entry = entry->next;
+        }
+    }
+
+    // XXX: the protocol doesn't allow variable size for the stack trace (yet)
+    *infoSize = (sizeof(size_t) * 2) + (sizeof(intptr_t) * BACKTRACE_SIZE);
+    *overallSize = *infoSize * gHashTable.count;
+    *backtraceSize = BACKTRACE_SIZE;
+
+    // now get a byte array big enough for this
+    *info = static_cast<uint8_t*>(dlmalloc(*overallSize));
+
+    if (*info == NULL) {
+        *overallSize = 0;
+        dlfree(list);
+        return;
+    }
+
+    qsort(list, gHashTable.count, sizeof(void*), hash_entry_compare);
+
+    uint8_t* head = *info;
+    const int count = gHashTable.count;
+    for (int i = 0 ; i < count ; ++i) {
+        HashEntry* entry = list[i];
+        size_t entrySize = (sizeof(size_t) * 2) + (sizeof(intptr_t) * entry->numEntries);
+        if (entrySize < *infoSize) {
+            /* we're writing less than a full entry, clear out the rest */
+            memset(head + entrySize, 0, *infoSize - entrySize);
+        } else {
+            /* make sure the amount we're copying doesn't exceed the limit */
+            entrySize = *infoSize;
+        }
+        memcpy(head, &(entry->size), entrySize);
+        head += *infoSize;
+    }
+
+    dlfree(list);
+}
+
+extern "C" void free_malloc_leak_info(uint8_t* info) {
+    dlfree(info);
+}
+
+extern "C" struct mallinfo mallinfo() {
+    return dlmallinfo();
+}
+
+extern "C" size_t malloc_usable_size(void* mem) {
+    return dlmalloc_usable_size(mem);
+}
+
+extern "C" void* valloc(size_t bytes) {
+    return dlvalloc(bytes);
+}
+
+extern "C" void* pvalloc(size_t bytes) {
+    return dlpvalloc(bytes);
+}
+
+extern "C" int posix_memalign(void** memptr, size_t alignment, size_t size) {
+    return dlposix_memalign(memptr, alignment, size);
+}
+
+/* Support for malloc debugging.
+ * Note that if USE_DL_PREFIX is not defined, it's assumed that memory
+ * allocation routines are implemented somewhere else, so all our custom
+ * malloc routines should not be compiled at all.
+ */
+#ifdef USE_DL_PREFIX
+
+/* Table for dispatching malloc calls, initialized with default dispatchers. */
+extern const MallocDebug __libc_malloc_default_dispatch;
+const MallocDebug __libc_malloc_default_dispatch __attribute__((aligned(32))) = {
+    dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign
+};
+
+/* Selector of dispatch table to use for dispatching malloc calls. */
+const MallocDebug* __libc_malloc_dispatch = &__libc_malloc_default_dispatch;
+
+extern "C" void* malloc(size_t bytes) {
+    return __libc_malloc_dispatch->malloc(bytes);
+}
+
+extern "C" void free(void* mem) {
+    __libc_malloc_dispatch->free(mem);
+}
+
+extern "C" void* calloc(size_t n_elements, size_t elem_size) {
+    return __libc_malloc_dispatch->calloc(n_elements, elem_size);
+}
+
+extern "C" void* realloc(void* oldMem, size_t bytes) {
+    return __libc_malloc_dispatch->realloc(oldMem, bytes);
+}
+
+extern "C" void* memalign(size_t alignment, size_t bytes) {
+    return __libc_malloc_dispatch->memalign(alignment, bytes);
+}
+
+/* We implement malloc debugging only in libc.so, so code bellow
+ * must be excluded if we compile this file for static libc.a
+ */
+#ifndef LIBC_STATIC
+#include <sys/system_properties.h>
+#include <dlfcn.h>
+#include <stdio.h>
+#include "logd.h"
+
+/* Table for dispatching malloc calls, depending on environment. */
+static MallocDebug gMallocUse __attribute__((aligned(32))) = {
+    dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign
+};
+
+extern char* __progname;
+
+/* Handle to shared library where actual memory allocation is implemented.
+ * This library is loaded and memory allocation calls are redirected there
+ * when libc.debug.malloc environment variable contains value other than
+ * zero:
+ * 1  - For memory leak detections.
+ * 5  - For filling allocated / freed memory with patterns defined by
+ *      CHK_SENTINEL_VALUE, and CHK_FILL_FREE macros.
+ * 10 - For adding pre-, and post- allocation stubs in order to detect
+ *      buffer overruns.
+ * Note that emulator's memory allocation instrumentation is not controlled by
+ * libc.debug.malloc value, but rather by emulator, started with -memcheck
+ * option. Note also, that if emulator has started with -memcheck option,
+ * emulator's instrumented memory allocation will take over value saved in
+ * libc.debug.malloc. In other words, if emulator has started with -memcheck
+ * option, libc.debug.malloc value is ignored.
+ * Actual functionality for debug levels 1-10 is implemented in
+ * libc_malloc_debug_leak.so, while functionality for emultor's instrumented
+ * allocations is implemented in libc_malloc_debug_qemu.so and can be run inside
+  * the emulator only.
+ */
+static void* libc_malloc_impl_handle = NULL;
+
+/* Make sure we have MALLOC_ALIGNMENT that matches the one that is
+ * used in dlmalloc. Emulator's memchecker needs this value to properly
+ * align its guarding zones.
+ */
+#ifndef MALLOC_ALIGNMENT
+#define MALLOC_ALIGNMENT ((size_t)8U)
+#endif  /* MALLOC_ALIGNMENT */
+
+/* This variable is set to the value of property libc.debug.malloc.backlog,
+ * when the value of libc.debug.malloc = 10.  It determines the size of the
+ * backlog we use to detect multiple frees.  If the property is not set, the
+ * backlog length defaults to an internal constant defined in
+ * malloc_debug_check.cpp.
+ */
+unsigned int malloc_double_free_backlog;
+
+static void InitMalloc(MallocDebug* table, int debug_level, const char* prefix) {
+  __libc_android_log_print(ANDROID_LOG_INFO, "libc", "%s: using libc.debug.malloc %d (%s)\n",
+                           __progname, debug_level, prefix);
+
+  char symbol[128];
+
+  snprintf(symbol, sizeof(symbol), "%s_malloc", prefix);
+  table->malloc = reinterpret_cast<MallocDebugMalloc>(dlsym(libc_malloc_impl_handle, symbol));
+  if (table->malloc == NULL) {
+      error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+  }
+
+  snprintf(symbol, sizeof(symbol), "%s_free", prefix);
+  table->free = reinterpret_cast<MallocDebugFree>(dlsym(libc_malloc_impl_handle, symbol));
+  if (table->free == NULL) {
+      error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+  }
+
+  snprintf(symbol, sizeof(symbol), "%s_calloc", prefix);
+  table->calloc = reinterpret_cast<MallocDebugCalloc>(dlsym(libc_malloc_impl_handle, symbol));
+  if (table->calloc == NULL) {
+      error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+  }
+
+  snprintf(symbol, sizeof(symbol), "%s_realloc", prefix);
+  table->realloc = reinterpret_cast<MallocDebugRealloc>(dlsym(libc_malloc_impl_handle, symbol));
+  if (table->realloc == NULL) {
+      error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+  }
+
+  snprintf(symbol, sizeof(symbol), "%s_memalign", prefix);
+  table->memalign = reinterpret_cast<MallocDebugMemalign>(dlsym(libc_malloc_impl_handle, symbol));
+  if (table->memalign == NULL) {
+      error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+  }
+}
+
+/* Initializes memory allocation framework once per process. */
+static void malloc_init_impl() {
+    const char* so_name = NULL;
+    MallocDebugInit malloc_debug_initialize = NULL;
+    unsigned int qemu_running = 0;
+    unsigned int debug_level = 0;
+    unsigned int memcheck_enabled = 0;
+    char env[PROP_VALUE_MAX];
+    char memcheck_tracing[PROP_VALUE_MAX];
+    char debug_program[PROP_VALUE_MAX];
+
+    /* Get custom malloc debug level. Note that emulator started with
+     * memory checking option will have priority over debug level set in
+     * libc.debug.malloc system property. */
+    if (__system_property_get("ro.kernel.qemu", env) && atoi(env)) {
+        qemu_running = 1;
+        if (__system_property_get("ro.kernel.memcheck", memcheck_tracing)) {
+            if (memcheck_tracing[0] != '0') {
+                // Emulator has started with memory tracing enabled. Enforce it.
+                debug_level = 20;
+                memcheck_enabled = 1;
+            }
+        }
+    }
+
+    /* If debug level has not been set by memcheck option in the emulator,
+     * lets grab it from libc.debug.malloc system property. */
+    if (debug_level == 0 && __system_property_get("libc.debug.malloc", env)) {
+        debug_level = atoi(env);
+    }
+
+    /* Debug level 0 means that we should use dlxxx allocation
+     * routines (default). */
+    if (debug_level == 0) {
+        return;
+    }
+
+    /* If libc.debug.malloc.program is set and is not a substring of progname,
+     * then exit.
+     */
+    if (__system_property_get("libc.debug.malloc.program", debug_program)) {
+        if (!strstr(__progname, debug_program)) {
+            return;
+        }
+    }
+
+    // Lets see which .so must be loaded for the requested debug level
+    switch (debug_level) {
+        case 1:
+        case 5:
+        case 10: {
+            char debug_backlog[PROP_VALUE_MAX];
+            if (__system_property_get("libc.debug.malloc.backlog", debug_backlog)) {
+                malloc_double_free_backlog = atoi(debug_backlog);
+                info_log("%s: setting backlog length to %d\n",
+                         __progname, malloc_double_free_backlog);
+            }
+
+            so_name = "/system/lib/libc_malloc_debug_leak.so";
+            break;
+        }
+        case 20:
+            // Quick check: debug level 20 can only be handled in emulator.
+            if (!qemu_running) {
+                error_log("%s: Debug level %d can only be set in emulator\n",
+                          __progname, debug_level);
+                return;
+            }
+            // Make sure that memory checking has been enabled in emulator.
+            if (!memcheck_enabled) {
+                error_log("%s: Memory checking is not enabled in the emulator\n",
+                          __progname);
+                return;
+            }
+            so_name = "/system/lib/libc_malloc_debug_qemu.so";
+            break;
+        default:
+            error_log("%s: Debug level %d is unknown\n",
+                      __progname, debug_level);
+            return;
+    }
+
+    // Load .so that implements the required malloc debugging functionality.
+    libc_malloc_impl_handle = dlopen(so_name, RTLD_LAZY);
+    if (libc_malloc_impl_handle == NULL) {
+        error_log("%s: Missing module %s required for malloc debug level %d: %s",
+                  __progname, so_name, debug_level, dlerror());
+        return;
+    }
+
+    // Initialize malloc debugging in the loaded module.
+    malloc_debug_initialize = reinterpret_cast<MallocDebugInit>(dlsym(libc_malloc_impl_handle,
+                                                                      "malloc_debug_initialize"));
+    if (malloc_debug_initialize == NULL) {
+        error_log("%s: Initialization routine is not found in %s\n",
+                  __progname, so_name);
+        dlclose(libc_malloc_impl_handle);
+        return;
+    }
+    if (malloc_debug_initialize()) {
+        dlclose(libc_malloc_impl_handle);
+        return;
+    }
+
+    if (debug_level == 20) {
+        // For memory checker we need to do extra initialization.
+        typedef int (*MemCheckInit)(int, const char*);
+        MemCheckInit memcheck_initialize =
+            reinterpret_cast<MemCheckInit>(dlsym(libc_malloc_impl_handle,
+                                                 "memcheck_initialize"));
+        if (memcheck_initialize == NULL) {
+            error_log("%s: memcheck_initialize routine is not found in %s\n",
+                      __progname, so_name);
+            dlclose(libc_malloc_impl_handle);
+            return;
+        }
+        if (memcheck_initialize(MALLOC_ALIGNMENT, memcheck_tracing)) {
+            dlclose(libc_malloc_impl_handle);
+            return;
+        }
+    }
+
+    // Initialize malloc dispatch table with appropriate routines.
+    switch (debug_level) {
+        case 1:
+            InitMalloc(&gMallocUse, debug_level, "leak");
+            break;
+        case 5:
+            InitMalloc(&gMallocUse, debug_level, "fill");
+            break;
+        case 10:
+            InitMalloc(&gMallocUse, debug_level, "chk");
+            break;
+        case 20:
+            InitMalloc(&gMallocUse, debug_level, "qemu_instrumented");
+            break;
+        default:
+            break;
+    }
+
+    // Make sure dispatch table is initialized
+    if ((gMallocUse.malloc == NULL) ||
+        (gMallocUse.free == NULL) ||
+        (gMallocUse.calloc == NULL) ||
+        (gMallocUse.realloc == NULL) ||
+        (gMallocUse.memalign == NULL)) {
+        error_log("%s: some symbols for libc.debug.malloc level %d were not found (see above)",
+                  __progname, debug_level);
+        dlclose(libc_malloc_impl_handle);
+        libc_malloc_impl_handle = NULL;
+    } else {
+        __libc_malloc_dispatch = &gMallocUse;
+    }
+}
+
+static void malloc_fini_impl() {
+    if (libc_malloc_impl_handle) {
+        MallocDebugFini malloc_debug_finalize =
+            reinterpret_cast<MallocDebugFini>(dlsym(libc_malloc_impl_handle,
+                                                    "malloc_debug_finalize"));
+        if (malloc_debug_finalize) {
+            malloc_debug_finalize();
+        }
+    }
+}
+
+static pthread_once_t  malloc_init_once_ctl = PTHREAD_ONCE_INIT;
+static pthread_once_t  malloc_fini_once_ctl = PTHREAD_ONCE_INIT;
+
+#endif  // !LIBC_STATIC
+#endif  // USE_DL_PREFIX
+
+/* Initializes memory allocation framework.
+ * This routine is called from __libc_init routines implemented
+ * in libc_init_static.c and libc_init_dynamic.c files.
+ */
+extern "C" void malloc_debug_init() {
+    /* We need to initialize malloc iff we implement here custom
+     * malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so */
+#if defined(USE_DL_PREFIX) && !defined(LIBC_STATIC)
+  if (pthread_once(&malloc_init_once_ctl, malloc_init_impl)) {
+        error_log("Unable to initialize malloc_debug component.");
+    }
+#endif  // USE_DL_PREFIX && !LIBC_STATIC
+}
+
+extern "C" void malloc_debug_fini() {
+  /* We need to finalize malloc iff we implement here custom
+     * malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so */
+#if defined(USE_DL_PREFIX) && !defined(LIBC_STATIC)
+  if (pthread_once(&malloc_fini_once_ctl, malloc_fini_impl)) {
+        error_log("Unable to finalize malloc_debug component.");
+    }
+#endif  // USE_DL_PREFIX && !LIBC_STATIC
+}