Consistently use strerror in libutils.

It's easier for people to debug, and side-steps the problem that errno
values differ between architectures.

Bug: http://b/17458391
Change-Id: I1db9b2cbb653839d3936b91e37e5cff02671318a

6 files changed, 31 insertions, 29 deletions

diff --git a/libutils/Looper.cpp b/libutils/Looper.cpp
index 9a2dd6cc4..20c1e927f 100644
--- a/libutils/Looper.cpp
+++ b/libutils/Looper.cpp
@@ -17,9 +17,11 @@
 #include <utils/Looper.h>
 #include <utils/Timers.h>
 
-#include <unistd.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
+#include <string.h>
+#include <unistd.h>
 
 
 namespace android {
@@ -71,32 +73,32 @@ Looper::Looper(bool allowNonCallbacks) :
         mResponseIndex(0), mNextMessageUptime(LLONG_MAX) {
     int wakeFds[2];
     int result = pipe(wakeFds);
-    LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe.  errno=%d", errno);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe: %s", strerror(errno));
 
     mWakeReadPipeFd = wakeFds[0];
     mWakeWritePipeFd = wakeFds[1];
 
     result = fcntl(mWakeReadPipeFd, F_SETFL, O_NONBLOCK);
-    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake read pipe non-blocking.  errno=%d",
-            errno);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake read pipe non-blocking: %s",
+            strerror(errno));
 
     result = fcntl(mWakeWritePipeFd, F_SETFL, O_NONBLOCK);
-    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake write pipe non-blocking.  errno=%d",
-            errno);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake write pipe non-blocking: %s",
+            strerror(errno));
 
     mIdling = false;
 
     // Allocate the epoll instance and register the wake pipe.
     mEpollFd = epoll_create(EPOLL_SIZE_HINT);
-    LOG_ALWAYS_FATAL_IF(mEpollFd < 0, "Could not create epoll instance.  errno=%d", errno);
+    LOG_ALWAYS_FATAL_IF(mEpollFd < 0, "Could not create epoll instance: %s", strerror(errno));
 
     struct epoll_event eventItem;
     memset(& eventItem, 0, sizeof(epoll_event)); // zero out unused members of data field union
     eventItem.events = EPOLLIN;
     eventItem.data.fd = mWakeReadPipeFd;
     result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mWakeReadPipeFd, & eventItem);
-    LOG_ALWAYS_FATAL_IF(result != 0, "Could not add wake read pipe to epoll instance.  errno=%d",
-            errno);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not add wake read pipe to epoll instance: %s",
+            strerror(errno));
 }
 
 Looper::~Looper() {
@@ -233,7 +235,7 @@ int Looper::pollInner(int timeoutMillis) {
         if (errno == EINTR) {
             goto Done;
         }
-        ALOGW("Poll failed with an unexpected error, errno=%d", errno);
+        ALOGW("Poll failed with an unexpected error: %s", strerror(errno));
         result = POLL_ERROR;
         goto Done;
     }
@@ -377,7 +379,7 @@ void Looper::wake() {
 
     if (nWrite != 1) {
         if (errno != EAGAIN) {
-            ALOGW("Could not write wake signal, errno=%d", errno);
+            ALOGW("Could not write wake signal: %s", strerror(errno));
         }
     }
 }
@@ -447,14 +449,14 @@ int Looper::addFd(int fd, int ident, int events, const sp<LooperCallback>& callb
         if (requestIndex < 0) {
             int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, fd, & eventItem);
             if (epollResult < 0) {
-                ALOGE("Error adding epoll events for fd %d, errno=%d", fd, errno);
+                ALOGE("Error adding epoll events for fd %d: %s", fd, strerror(errno));
                 return -1;
             }
             mRequests.add(fd, request);
         } else {
             int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_MOD, fd, & eventItem);
             if (epollResult < 0) {
-                ALOGE("Error modifying epoll events for fd %d, errno=%d", fd, errno);
+                ALOGE("Error modifying epoll events for fd %d: %s", fd, strerror(errno));
                 return -1;
             }
             mRequests.replaceValueAt(requestIndex, request);
@@ -477,7 +479,7 @@ int Looper::removeFd(int fd) {
 
         int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, NULL);
         if (epollResult < 0) {
-            ALOGE("Error removing epoll events for fd %d, errno=%d", fd, errno);
+            ALOGE("Error removing epoll events for fd %d: %s", fd, strerror(errno));
             return -1;
         }
 
diff --git a/libutils/ProcessCallStack.cpp b/libutils/ProcessCallStack.cpp
index db07e563f..011c30291 100644
--- a/libutils/ProcessCallStack.cpp
+++ b/libutils/ProcessCallStack.cpp
@@ -17,9 +17,10 @@
 #define LOG_TAG "ProcessCallStack"
 // #define LOG_NDEBUG 0
 
-#include <string.h>
-#include <stdio.h>
 #include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
 
 #include <utils/Log.h>
 #include <utils/Errors.h>
@@ -135,8 +136,8 @@ void ProcessCallStack::update() {
 
     dp = opendir(PATH_SELF_TASK);
     if (dp == NULL) {
-        ALOGE("%s: Failed to update the process's call stacks (errno = %d, '%s')",
-              __FUNCTION__, errno, strerror(errno));
+        ALOGE("%s: Failed to update the process's call stacks: %s",
+              __FUNCTION__, strerror(errno));
         return;
     }
 
@@ -172,8 +173,8 @@ void ProcessCallStack::update() {
 
         ssize_t idx = mThreadMap.add(tid, ThreadInfo());
         if (idx < 0) { // returns negative error value on error
-            ALOGE("%s: Failed to add new ThreadInfo (errno = %zd, '%s')",
-                  __FUNCTION__, idx, strerror(-idx));
+            ALOGE("%s: Failed to add new ThreadInfo: %s",
+                  __FUNCTION__, strerror(-idx));
             continue;
         }
 
@@ -195,8 +196,8 @@ void ProcessCallStack::update() {
               __FUNCTION__, tid, threadInfo.callStack.size());
     }
     if (code != 0) { // returns positive error value on error
-        ALOGE("%s: Failed to readdir from %s (errno = %d, '%s')",
-              __FUNCTION__, PATH_SELF_TASK, -code, strerror(code));
+        ALOGE("%s: Failed to readdir from %s: %s",
+              __FUNCTION__, PATH_SELF_TASK, strerror(code));
     }
 #endif
 
diff --git a/libutils/SystemClock.cpp b/libutils/SystemClock.cpp
index ac3dd987b..64204a8e8 100644
--- a/libutils/SystemClock.cpp
+++ b/libutils/SystemClock.cpp
@@ -29,7 +29,6 @@
 #include <sys/time.h>
 #include <limits.h>
 #include <fcntl.h>
-#include <errno.h>
 #include <string.h>
 
 #include <utils/SystemClock.h>
diff --git a/libutils/Threads.cpp b/libutils/Threads.cpp
index 1e014c64e..c3666e4b4 100644
--- a/libutils/Threads.cpp
+++ b/libutils/Threads.cpp
@@ -22,6 +22,7 @@
 #include <memory.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 
 #if !defined(_WIN32)
@@ -160,9 +161,9 @@ int androidCreateRawThreadEtc(android_thread_func_t entryFunction,
                     (android_pthread_entry)entryFunction, userData);
     pthread_attr_destroy(&attr);
     if (result != 0) {
-        ALOGE("androidCreateRawThreadEtc failed (entry=%p, res=%d, errno=%d)\n"
+        ALOGE("androidCreateRawThreadEtc failed (entry=%p, res=%d, %s)\n"
              "(android threadPriority=%d)",
-            entryFunction, result, errno, threadPriority);
+            entryFunction, result, strerror(errno), threadPriority);
         return 0;
     }
 
diff --git a/libutils/Tokenizer.cpp b/libutils/Tokenizer.cpp
index 610002fe3..2d0e83dcd 100644
--- a/libutils/Tokenizer.cpp
+++ b/libutils/Tokenizer.cpp
@@ -56,12 +56,12 @@ status_t Tokenizer::open(const String8& filename, Tokenizer** outTokenizer) {
     int fd = ::open(filename.string(), O_RDONLY);
     if (fd < 0) {
         result = -errno;
-        ALOGE("Error opening file '%s', %s.", filename.string(), strerror(errno));
+        ALOGE("Error opening file '%s': %s", filename.string(), strerror(errno));
     } else {
         struct stat stat;
         if (fstat(fd, &stat)) {
             result = -errno;
-            ALOGE("Error getting size of file '%s', %s.", filename.string(), strerror(errno));
+            ALOGE("Error getting size of file '%s': %s", filename.string(), strerror(errno));
         } else {
             size_t length = size_t(stat.st_size);
 
@@ -83,7 +83,7 @@ status_t Tokenizer::open(const String8& filename, Tokenizer** outTokenizer) {
                 ssize_t nrd = read(fd, buffer, length);
                 if (nrd < 0) {
                     result = -errno;
-                    ALOGE("Error reading file '%s', %s.", filename.string(), strerror(errno));
+                    ALOGE("Error reading file '%s': %s", filename.string(), strerror(errno));
                     delete[] buffer;
                     buffer = NULL;
                 } else {
diff --git a/libutils/misc.cpp b/libutils/misc.cpp
index ed1ba2392..216dc1430 100644
--- a/libutils/misc.cpp
+++ b/libutils/misc.cpp
@@ -24,7 +24,6 @@
 
 #include <sys/stat.h>
 #include <string.h>
-#include <errno.h>
 #include <stdio.h>
 
 #if !defined(_WIN32)