ueventd: convert mkdir_recursive() to std::string

Bug: 36250207

Test: Boot bullhead
Test: Boot sailfish, observe no boot time regression
Test: init unit tests

Change-Id: I5a2ac369d846e044230b709fd07eb21ad12d47bb

init/Android.mk

@@ -148,8 +148,9 @@ LOCAL_SRC_FILES := \
     util_test.cpp \
 
 LOCAL_SHARED_LIBRARIES += \
-    libcutils \
     libbase \
+    libcutils \
+    libselinux \
 
 LOCAL_STATIC_LIBRARIES := libinit
 LOCAL_SANITIZE := integer

init/util.cpp

@@ -194,37 +194,18 @@ bool write_file(const std::string& path, const std::string& content) {
     return success;
 }
 
-int mkdir_recursive(const char *pathname, mode_t mode)
-{
-    char buf[128];
-    const char *slash;
-    const char *p = pathname;
-    int width;
-    int ret;
-    struct stat info;
-
-    while ((slash = strchr(p, '/')) != NULL) {
-        width = slash - pathname;
-        p = slash + 1;
-        if (width < 0)
-            break;
-        if (width == 0)
-            continue;
-        if ((unsigned int)width > sizeof(buf) - 1) {
-            LOG(ERROR) << "path too long for mkdir_recursive";
-            return -1;
-        }
-        memcpy(buf, pathname, width);
-        buf[width] = 0;
-        if (stat(buf, &info) != 0) {
-            ret = make_dir(buf, mode);
-            if (ret && errno != EEXIST)
-                return ret;
+int mkdir_recursive(const std::string& path, mode_t mode) {
+    std::string::size_type slash = 0;
+    while ((slash = path.find('/', slash + 1)) != std::string::npos) {
+        auto directory = path.substr(0, slash);
+        struct stat info;
+        if (stat(directory.c_str(), &info) != 0) {
+            auto ret = make_dir(directory.c_str(), mode);
+            if (ret && errno != EEXIST) return ret;
         }
     }
-    ret = make_dir(pathname, mode);
-    if (ret && errno != EEXIST)
-        return ret;
+    auto ret = make_dir(path.c_str(), mode);
+    if (ret && errno != EEXIST) return ret;
     return 0;
 }
 

init/util.h

@@ -60,7 +60,7 @@ std::ostream& operator<<(std::ostream& os, const Timer& t);
 
 unsigned int decode_uid(const char *s);
 
-int mkdir_recursive(const char *pathname, mode_t mode);
+int mkdir_recursive(const std::string& pathname, mode_t mode);
 int wait_for_file(const char *filename, std::chrono::nanoseconds timeout);
 void import_kernel_cmdline(bool in_qemu,
                            const std::function<void(const std::string&, const std::string&, bool)>&);

init/util_test.cpp

@@ -120,3 +120,39 @@ TEST(util, decode_uid) {
   EXPECT_EQ(UINT_MAX, decode_uid("toot"));
   EXPECT_EQ(123U, decode_uid("123"));
 }
+
+TEST(util, is_dir) {
+    TemporaryDir test_dir;
+    EXPECT_TRUE(is_dir(test_dir.path));
+    TemporaryFile tf;
+    EXPECT_FALSE(is_dir(tf.path));
+}
+
+// sehandle is needed for make_dir()
+// TODO: Remove once sehandle is encapsulated
+#include <selinux/label.h>
+selabel_handle* sehandle;
+
+TEST(util, mkdir_recursive) {
+    TemporaryDir test_dir;
+    std::string path = android::base::StringPrintf("%s/three/directories/deep", test_dir.path);
+    EXPECT_EQ(0, mkdir_recursive(path, 0755));
+    std::string path1 = android::base::StringPrintf("%s/three", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+    std::string path2 = android::base::StringPrintf("%s/three/directories", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+    std::string path3 = android::base::StringPrintf("%s/three/directories/deep", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+}
+
+TEST(util, mkdir_recursive_extra_slashes) {
+    TemporaryDir test_dir;
+    std::string path = android::base::StringPrintf("%s/three////directories/deep//", test_dir.path);
+    EXPECT_EQ(0, mkdir_recursive(path, 0755));
+    std::string path1 = android::base::StringPrintf("%s/three", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+    std::string path2 = android::base::StringPrintf("%s/three/directories", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+    std::string path3 = android::base::StringPrintf("%s/three/directories/deep", test_dir.path);
+    EXPECT_TRUE(is_dir(path1.c_str()));
+}