Merge "fs_config supports shell wildcard patterns"

4 files changed, 58 insertions, 30 deletions

diff --git a/libcutils/Android.bp b/libcutils/Android.bp
index fab4b4e25..17c8a13b3 100644
--- a/libcutils/Android.bp
+++ b/libcutils/Android.bp
@@ -60,7 +60,6 @@ cc_library {
     host_supported: true,
     srcs: [
         "config_utils.cpp",
-        "fs_config.cpp",
         "canned_fs_config.cpp",
         "iosched_policy.cpp",
         "load_file.cpp",
@@ -80,6 +79,7 @@ cc_library {
         not_windows: {
             srcs: libcutils_nonwindows_sources + [
                 "ashmem-host.cpp",
+                "fs_config.cpp",
                 "trace-host.cpp",
             ],
         },
@@ -104,6 +104,7 @@ cc_library {
             srcs: libcutils_nonwindows_sources + [
                 "android_reboot.cpp",
                 "ashmem-dev.cpp",
+                "fs_config.cpp",
                 "klog.cpp",
                 "partition_utils.cpp",
                 "properties.cpp",
diff --git a/libcutils/fs_config.cpp b/libcutils/fs_config.cpp
index c95868dd9..618481361 100644
--- a/libcutils/fs_config.cpp
+++ b/libcutils/fs_config.cpp
@@ -24,6 +24,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <fnmatch.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -31,6 +32,9 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <string>
+
+#include <android-base/strings.h>
 #include <log/log.h>
 #include <private/android_filesystem_config.h>
 #include <utils/Compat.h>
@@ -39,6 +43,9 @@
 #define O_BINARY 0
 #endif
 
+using android::base::EndsWith;
+using android::base::StartsWith;
+
 // My kingdom for <endian.h>
 static inline uint16_t get2LE(const uint8_t* src) {
     return src[0] | (src[1] << 8);
@@ -259,46 +266,55 @@ static int fs_config_open(int dir, int which, const char* target_out_path) {
 
 // if path is "odm/<stuff>", "oem/<stuff>", "product/<stuff>",
 // "product_services/<stuff>" or "vendor/<stuff>"
-static bool is_partition(const char* path, size_t len) {
+static bool is_partition(const std::string& path) {
     static const char* partitions[] = {"odm/", "oem/", "product/", "product_services/", "vendor/"};
     for (size_t i = 0; i < (sizeof(partitions) / sizeof(partitions[0])); ++i) {
-        size_t plen = strlen(partitions[i]);
-        if (len <= plen) continue;
-        if (!strncmp(path, partitions[i], plen)) return true;
+        if (StartsWith(path, partitions[i])) return true;
     }
     return false;
 }
 
-static inline bool prefix_cmp(bool partial, const char* prefix, size_t len, const char* path,
-                              size_t plen) {
-    return ((partial && plen >= len) || (plen == len)) && !strncmp(prefix, path, len);
-}
-
 // alias prefixes of "<partition>/<stuff>" to "system/<partition>/<stuff>" or
 // "system/<partition>/<stuff>" to "<partition>/<stuff>"
-static bool fs_config_cmp(bool partial, const char* prefix, size_t len, const char* path,
-                          size_t plen) {
-    // If name ends in * then allow partial matches.
-    if (!partial && prefix[len - 1] == '*') {
-        len--;
-        partial = true;
+static bool fs_config_cmp(bool dir, const char* prefix, size_t len, const char* path, size_t plen) {
+    std::string pattern(prefix, len);
+    std::string input(path, plen);
+
+    // Massage pattern and input so that they can be used by fnmatch where
+    // directories have to end with /.
+    if (dir) {
+        if (!EndsWith(input, "/")) {
+            input.append("/");
+        }
+
+        if (!EndsWith(pattern, "/*")) {
+            if (EndsWith(pattern, "/")) {
+                pattern.append("*");
+            } else {
+                pattern.append("/*");
+            }
+        }
     }
 
-    if (prefix_cmp(partial, prefix, len, path, plen)) return true;
+    // no FNM_PATHNAME is set in order to match a/b/c/d with a/*
+    // FNM_ESCAPE is set in order to prevent using \\? and \\* and maintenance issues.
+    const int fnm_flags = FNM_NOESCAPE;
+    if (fnmatch(pattern.c_str(), input.c_str(), fnm_flags) == 0) return true;
 
-    static const char system[] = "system/";
-    if (!strncmp(path, system, strlen(system))) {
-        path += strlen(system);
-        plen -= strlen(system);
-    } else if (len <= strlen(system)) {
-        return false;
-    } else if (strncmp(prefix, system, strlen(system))) {
+    static constexpr const char* kSystem = "system/";
+    if (StartsWith(input, kSystem)) {
+        input.erase(0, strlen(kSystem));
+    } else if (input.size() <= strlen(kSystem)) {
         return false;
+    } else if (StartsWith(pattern, kSystem)) {
+        pattern.erase(0, strlen(kSystem));
     } else {
-        prefix += strlen(system);
-        len -= strlen(system);
+        return false;
     }
-    return is_partition(prefix, len) && prefix_cmp(partial, prefix, len, path, plen);
+
+    if (!is_partition(pattern)) return false;
+    if (!is_partition(input)) return false;
+    return fnmatch(pattern.c_str(), input.c_str(), fnm_flags) == 0;
 }
 #ifndef __ANDROID_VNDK__
 auto __for_testing_only__fs_config_cmp = fs_config_cmp;
diff --git a/libcutils/tests/Android.bp b/libcutils/tests/Android.bp
index fb9bbdd92..3892ce012 100644
--- a/libcutils/tests/Android.bp
+++ b/libcutils/tests/Android.bp
@@ -20,6 +20,7 @@ cc_defaults {
         android: {
             srcs: [
                 "AshmemTest.cpp",
+                "fs_config.cpp",
                 "MemsetTest.cpp",
                 "PropertiesTest.cpp",
                 "sched_policy_test.cpp",
@@ -28,13 +29,13 @@ cc_defaults {
                 "android_get_control_socket_test.cpp",
                 "android_get_control_file_test.cpp",
                 "multiuser_test.cpp",
-                "fs_config.cpp",
             ],
         },
 
         not_windows: {
             srcs: [
                 "test_str_parms.cpp",
+                "fs_config.cpp",
             ],
         },
     },
diff --git a/libcutils/tests/fs_config.cpp b/libcutils/tests/fs_config.cpp
index d5dc66a97..c26315fea 100644
--- a/libcutils/tests/fs_config.cpp
+++ b/libcutils/tests/fs_config.cpp
@@ -42,11 +42,15 @@ static const struct fs_config_cmp_test {
     const char* path;
     bool match;
 } fs_config_cmp_tests[] = {
-    // clang-format off
+        // clang-format off
     { true,  "system/lib",             "system/lib/hw",           true  },
     { true,  "vendor/lib",             "system/vendor/lib/hw",    true  },
     { true,  "system/vendor/lib",      "vendor/lib/hw",           true  },
     { true,  "system/vendor/lib",      "system/vendor/lib/hw",    true  },
+    { true,  "foo/*/bar/*",            "foo/1/bar/2",             true  },
+    { true,  "foo/*/bar/*",            "foo/1/bar",               true  },
+    { true,  "foo/*/bar/*",            "foo/1/bar/2/3",           true  },
+    { true,  "foo/*/bar/*",            "foo/1/bar/2/3/",          true  },
     { false, "vendor/bin/wifi",        "system/vendor/bin/w",     false },
     { false, "vendor/bin/wifi",        "system/vendor/bin/wifi",  true  },
     { false, "vendor/bin/wifi",        "system/vendor/bin/wifi2", false },
@@ -58,8 +62,14 @@ static const struct fs_config_cmp_test {
     { false, "vendor/bin/*",           "system/vendor/bin/wifi",  true  },
     { false, "system/bin/*",           "system/bin",              false },
     { false, "system/vendor/bin/*",    "vendor/bin/wifi",         true  },
+    { false, "foo/*/bar/*",            "foo/1/bar/2",             true  },
+    { false, "foo/*/bar/*",            "foo/1/bar",               false },
+    { false, "foo/*/bar/*",            "foo/1/bar/2/3",           true  },
+    { false, "foo/*/bar/*.so",         "foo/1/bar/2/3",           false },
+    { false, "foo/*/bar/*.so",         "foo/1/bar/2.so",          true  },
+    { false, "foo/*/bar/*.so",         "foo/1/bar/2/3.so",        true  },
     { false, NULL,                     NULL,                      false },
-    // clang-format on
+        // clang-format on
 };
 
 static bool check_unique(std::vector<const char*>& paths, const std::string& config_name,