Move libcutils source to C++.

Just the minimial changes to get this to actually build, because otherwise
we always bog down trying to rewrite everything (when the real answer
is usually "stop using libcutils, it's awful").

This doesn't move a handful of files: two are basically just BSD libc
source, a couple have outstanding code reviews, and one can be deleted
(but I'll do that in a separate change).

I'm also skipping the presubmit hooks because otherwise clang-format
wants to reformat everything. I'll follow up with that...

Bug: N/A
Test: builds
Change-Id: I06403f465b67c8e493bad466dd76b1151eed5993

1 files changed, 168 insertions, 0 deletions

diff --git a/libcutils/socket_local_client_unix.cpp b/libcutils/socket_local_client_unix.cpp
new file mode 100644
index 000000000..68b2b0ce9
--- /dev/null
+++ b/libcutils/socket_local_client_unix.cpp
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <cutils/sockets.h>
+
+#include <errno.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#if defined(_WIN32)
+
+int socket_local_client(const char *name, int namespaceId, int type)
+{
+    errno = ENOSYS;
+    return -1;
+}
+
+#else /* !_WIN32 */
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/select.h>
+#include <sys/types.h>
+
+#include "socket_local_unix.h"
+
+#define UNUSED __attribute__((unused))
+
+#define LISTEN_BACKLOG 4
+
+/* Documented in header file. */
+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;
+    }
+
+    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
+ */
+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
+ */
+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);
+        return -1;
+    }
+
+    return s;
+}
+
+#endif /* !_WIN32 */