liblog: simplify socket_local_client() and always use CLOEXEC

socket_local_client() was copied from libcutils, but we only need a
small subset of its functionality.  We instead create our own version
with just the needed parts.

Importantly, use CLOEXEC in this new function and other places where
it was missing previously.

Test: logging works, liblog-unit-tests
Change-Id: Ifb929227af67bafa13e391eab92358d9f6fe6450
diff --git a/liblog/logd_reader.cpp b/liblog/logd_reader.cpp
index 2f0af4a..b7ba782 100644
--- a/liblog/logd_reader.cpp
+++ b/liblog/logd_reader.cpp
@@ -100,148 +100,29 @@
   return -EBADF;
 }
 
-/* Private copy of ../libcutils/socket_local_client.c prevent library loops */
+// Connects to /dev/socket/<name> and returns the associated fd or returns -1 on error.
+// O_CLOEXEC is always set.
+static int socket_local_client(const std::string& name, int type) {
+  sockaddr_un addr = {.sun_family = AF_LOCAL};
 
-#if defined(_WIN32)
-
-LIBLOG_WEAK int socket_local_client(const char* name, int namespaceId, int type) {
-  errno = ENOSYS;
-  return -ENOSYS;
-}
-
-#else /* !_WIN32 */
-
-#include <sys/select.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-#include <sys/un.h>
-
-/* Private copy of ../libcutils/socket_local.h prevent library loops */
-#define FILESYSTEM_SOCKET_PREFIX "/tmp/"
-#define ANDROID_RESERVED_SOCKET_PREFIX "/dev/socket/"
-/* End of ../libcutils/socket_local.h */
-
-#define LISTEN_BACKLOG 4
-
-/* Documented in header file. */
-LIBLOG_WEAK int socket_make_sockaddr_un(const char* name, int namespaceId,
-                                        struct sockaddr_un* p_addr, socklen_t* alen) {
-  memset(p_addr, 0, sizeof(*p_addr));
-  size_t namelen;
-
-  switch (namespaceId) {
-    case ANDROID_SOCKET_NAMESPACE_ABSTRACT:
-#if defined(__linux__)
-      namelen = strlen(name);
-
-      /* Test with length +1 for the *initial* '\0'. */
-      if ((namelen + 1) > sizeof(p_addr->sun_path)) {
-        goto error;
-      }
-
-      /*
-       * Note: The path in this case is *not* supposed to be
-       * '\0'-terminated. ("man 7 unix" for the gory details.)
-       */
-
-      p_addr->sun_path[0] = 0;
-      memcpy(p_addr->sun_path + 1, name, namelen);
-#else
-      /* this OS doesn't have the Linux abstract namespace */
-
-      namelen = strlen(name) + strlen(FILESYSTEM_SOCKET_PREFIX);
-      /* unix_path_max appears to be missing on linux */
-      if (namelen > sizeof(*p_addr) - offsetof(struct sockaddr_un, sun_path) - 1) {
-        goto error;
-      }
-
-      strcpy(p_addr->sun_path, FILESYSTEM_SOCKET_PREFIX);
-      strcat(p_addr->sun_path, name);
-#endif
-      break;
-
-    case ANDROID_SOCKET_NAMESPACE_RESERVED:
-      namelen = strlen(name) + strlen(ANDROID_RESERVED_SOCKET_PREFIX);
-      /* unix_path_max appears to be missing on linux */
-      if (namelen > sizeof(*p_addr) - offsetof(struct sockaddr_un, sun_path) - 1) {
-        goto error;
-      }
-
-      strcpy(p_addr->sun_path, ANDROID_RESERVED_SOCKET_PREFIX);
-      strcat(p_addr->sun_path, name);
-      break;
-
-    case ANDROID_SOCKET_NAMESPACE_FILESYSTEM:
-      namelen = strlen(name);
-      /* unix_path_max appears to be missing on linux */
-      if (namelen > sizeof(*p_addr) - offsetof(struct sockaddr_un, sun_path) - 1) {
-        goto error;
-      }
-
-      strcpy(p_addr->sun_path, name);
-      break;
-
-    default:
-      /* invalid namespace id */
-      return -1;
+  std::string path = "/dev/socket/" + name;
+  if (path.size() + 1 > sizeof(addr.sun_path)) {
+    return -1;
   }
+  strlcpy(addr.sun_path, path.c_str(), sizeof(addr.sun_path));
 
-  p_addr->sun_family = AF_LOCAL;
-  *alen = namelen + offsetof(struct sockaddr_un, sun_path) + 1;
-  return 0;
-error:
-  return -1;
-}
-
-/**
- * connect to peer named "name" on fd
- * returns same fd or -1 on error.
- * fd is not closed on error. that's your job.
- *
- * Used by AndroidSocketImpl
- */
-LIBLOG_WEAK int socket_local_client_connect(int fd, const char* name, int namespaceId,
-                                            int type __unused) {
-  struct sockaddr_un addr;
-  socklen_t alen;
-  int err;
-
-  err = socket_make_sockaddr_un(name, namespaceId, &addr, &alen);
-
-  if (err < 0) {
-    goto error;
-  }
-
-  if (connect(fd, (struct sockaddr*)&addr, alen) < 0) {
-    goto error;
-  }
-
-  return fd;
-
-error:
-  return -1;
-}
-
-/**
- * connect to peer named "name"
- * returns fd or -1 on error
- */
-LIBLOG_WEAK int socket_local_client(const char* name, int namespaceId, int type) {
-  int s;
-
-  s = socket(AF_LOCAL, type, 0);
-  if (s < 0) return -1;
-
-  if (0 > socket_local_client_connect(s, name, namespaceId, type)) {
-    close(s);
+  int fd = socket(AF_LOCAL, type | SOCK_CLOEXEC, 0);
+  if (fd == 0) {
     return -1;
   }
 
-  return s;
-}
+  if (connect(fd, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)) == -1) {
+    close(fd);
+    return -1;
+  }
 
-#endif /* !_WIN32 */
-/* End of ../libcutils/socket_local_client.c */
+  return fd;
+}
 
 /* worker for sending the command to the logger */
 static ssize_t send_log_msg(struct android_log_logger* logger, const char* msg, char* buf,
@@ -250,7 +131,7 @@
   size_t len;
   char* cp;
   int errno_save = 0;
-  int sock = socket_local_client("logd", ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_STREAM);
+  int sock = socket_local_client("logd", SOCK_STREAM);
   if (sock < 0) {
     return sock;
   }
@@ -460,10 +341,10 @@
     return sock;
   }
 
-  sock = socket_local_client("logdr", ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET);
+  sock = socket_local_client("logdr", SOCK_SEQPACKET);
   if (sock == 0) {
     /* Guarantee not file descriptor zero */
-    int newsock = socket_local_client("logdr", ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET);
+    int newsock = socket_local_client("logdr", SOCK_SEQPACKET);
     close(sock);
     sock = newsock;
   }
diff --git a/liblog/tests/Android.bp b/liblog/tests/Android.bp
index 4ab2acb..50755ce 100644
--- a/liblog/tests/Android.bp
+++ b/liblog/tests/Android.bp
@@ -31,6 +31,7 @@
     shared_libs: [
         "libm",
         "libbase",
+        "libcutils",
     ],
     static_libs: ["liblog"],
     srcs: ["liblog_benchmark.cpp"],
diff --git a/liblog/tests/libc_test.cpp b/liblog/tests/libc_test.cpp
index 6d78ed6..3534eb8 100644
--- a/liblog/tests/libc_test.cpp
+++ b/liblog/tests/libc_test.cpp
@@ -23,7 +23,7 @@
 #ifdef __ANDROID__
 #ifndef NO_PSTORE
   FILE* fp;
-  ASSERT_TRUE(NULL != (fp = fopen("/dev/pmsg0", "a")));
+  ASSERT_TRUE(NULL != (fp = fopen("/dev/pmsg0", "ae")));
   static const char message[] = "libc.__pstore_append\n";
   ASSERT_EQ((size_t)1, fwrite(message, sizeof(message), 1, fp));
   int fflushReturn = fflush(fp);
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index c8ac321..7d11ccf 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -172,7 +172,7 @@
  * Measure the time it takes to submit the android logging data to pstore
  */
 static void BM_pmsg_short(benchmark::State& state) {
-  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY));
+  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY | O_CLOEXEC));
   if (pstore_fd < 0) {
     state.SkipWithError("/dev/pmsg0");
     return;
@@ -248,7 +248,7 @@
  * best case aligned single block.
  */
 static void BM_pmsg_short_aligned(benchmark::State& state) {
-  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY));
+  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY | O_CLOEXEC));
   if (pstore_fd < 0) {
     state.SkipWithError("/dev/pmsg0");
     return;
@@ -323,7 +323,7 @@
  * best case aligned single block.
  */
 static void BM_pmsg_short_unaligned1(benchmark::State& state) {
-  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY));
+  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY | O_CLOEXEC));
   if (pstore_fd < 0) {
     state.SkipWithError("/dev/pmsg0");
     return;
@@ -398,7 +398,7 @@
  * best case aligned single block.
  */
 static void BM_pmsg_long_aligned(benchmark::State& state) {
-  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY));
+  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY | O_CLOEXEC));
   if (pstore_fd < 0) {
     state.SkipWithError("/dev/pmsg0");
     return;
@@ -471,7 +471,7 @@
  * best case aligned single block.
  */
 static void BM_pmsg_long_unaligned1(benchmark::State& state) {
-  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY));
+  int pstore_fd = TEMP_FAILURE_RETRY(open("/dev/pmsg0", O_WRONLY | O_CLOEXEC));
   if (pstore_fd < 0) {
     state.SkipWithError("/dev/pmsg0");
     return;
@@ -949,8 +949,8 @@
 
 // Must be functionally identical to liblog internal __send_log_msg.
 static void send_to_control(char* buf, size_t len) {
-  int sock = socket_local_client("logd", ANDROID_SOCKET_NAMESPACE_RESERVED,
-                                 SOCK_STREAM);
+  int sock =
+      socket_local_client("logd", ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_STREAM | SOCK_CLOEXEC);
   if (sock < 0) return;
   size_t writeLen = strlen(buf) + 1;
 
diff --git a/liblog/tests/liblog_test.cpp b/liblog/tests/liblog_test.cpp
index 83f0fa9..1f87b3e 100644
--- a/liblog/tests/liblog_test.cpp
+++ b/liblog/tests/liblog_test.cpp
@@ -93,7 +93,7 @@
 static std::string popenToString(const std::string& command) {
   std::string ret;
 
-  FILE* fp = popen(command.c_str(), "r");
+  FILE* fp = popen(command.c_str(), "re");
   if (fp) {
     if (!android::base::ReadFdToString(fileno(fp), &ret)) ret = "";
     pclose(fp);
@@ -645,7 +645,7 @@
   char buffer[512];
   snprintf(buffer, sizeof(buffer), "/proc/%u/stat", pid);
 
-  FILE* fp = fopen(buffer, "r");
+  FILE* fp = fopen(buffer, "re");
   if (!fp) {
     return;
   }
diff --git a/liblog/tests/log_radio_test.cpp b/liblog/tests/log_radio_test.cpp
index f202c67..fa1255e 100644
--- a/liblog/tests/log_radio_test.cpp
+++ b/liblog/tests/log_radio_test.cpp
@@ -91,7 +91,7 @@
       "logcat -b radio --pid=%u -d -s"
       " TEST__RLOGV TEST__RLOGD TEST__RLOGI TEST__RLOGW TEST__RLOGE",
       (unsigned)getpid());
-  FILE* fp = popen(buf.c_str(), "r");
+  FILE* fp = popen(buf.c_str(), "re");
   int count = 0;
   int count_false = 0;
   if (fp) {
diff --git a/liblog/tests/log_system_test.cpp b/liblog/tests/log_system_test.cpp
index 0656c0b..13f026d 100644
--- a/liblog/tests/log_system_test.cpp
+++ b/liblog/tests/log_system_test.cpp
@@ -91,7 +91,7 @@
       "logcat -b system --pid=%u -d -s"
       " TEST__SLOGV TEST__SLOGD TEST__SLOGI TEST__SLOGW TEST__SLOGE",
       (unsigned)getpid());
-  FILE* fp = popen(buf.c_str(), "r");
+  FILE* fp = popen(buf.c_str(), "re");
   int count = 0;
   int count_false = 0;
   if (fp) {