Merge "TEST_MAPPING: fix TODO syntax" into main
diff --git a/core/config.mk b/core/config.mk
index e37f010..daefa70 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -420,12 +420,9 @@
 .KATI_READONLY := TARGET_MAX_PAGE_SIZE_SUPPORTED
 
 # Boolean variable determining if AOSP relies on bionic's PAGE_SIZE macro.
+TARGET_NO_BIONIC_PAGE_SIZE_MACRO := false
 ifdef PRODUCT_NO_BIONIC_PAGE_SIZE_MACRO
   TARGET_NO_BIONIC_PAGE_SIZE_MACRO := $(PRODUCT_NO_BIONIC_PAGE_SIZE_MACRO)
-else ifeq ($(call math_lt,$(VSR_VENDOR_API_LEVEL),34),true)
-  TARGET_NO_BIONIC_PAGE_SIZE_MACRO := false
-else
-  TARGET_NO_BIONIC_PAGE_SIZE_MACRO := true
 endif
 .KATI_READONLY := TARGET_NO_BIONIC_PAGE_SIZE_MACRO
 
diff --git a/tools/aconfig/aconfig/src/storage/flag_table.rs b/tools/aconfig/aconfig/src/storage/flag_table.rs
index b861c1f..d4f4bc2 100644
--- a/tools/aconfig/aconfig/src/storage/flag_table.rs
+++ b/tools/aconfig/aconfig/src/storage/flag_table.rs
@@ -17,7 +17,7 @@
 use crate::commands::assign_flag_ids;
 use crate::storage::FlagPackage;
 use aconfig_storage_file::{
-    get_table_size, FlagTable, FlagTableHeader, FlagTableNode, FILE_VERSION, StorageFileType
+    get_table_size, FlagTable, FlagTableHeader, FlagTableNode, StorageFileType, FILE_VERSION,
 };
 use anyhow::{anyhow, Result};
 
diff --git a/tools/aconfig/aconfig/src/storage/flag_value.rs b/tools/aconfig/aconfig/src/storage/flag_value.rs
index e40bbc1..293615e 100644
--- a/tools/aconfig/aconfig/src/storage/flag_value.rs
+++ b/tools/aconfig/aconfig/src/storage/flag_value.rs
@@ -17,7 +17,7 @@
 use crate::commands::assign_flag_ids;
 use crate::storage::FlagPackage;
 use aconfig_protos::ProtoFlagState;
-use aconfig_storage_file::{FlagValueHeader, FlagValueList, FILE_VERSION, StorageFileType};
+use aconfig_storage_file::{FlagValueHeader, FlagValueList, StorageFileType, FILE_VERSION};
 use anyhow::{anyhow, Result};
 
 fn new_header(container: &str, num_flags: u32) -> FlagValueHeader {
diff --git a/tools/aconfig/aconfig/src/storage/mod.rs b/tools/aconfig/aconfig/src/storage/mod.rs
index c818d79..3f5f8de 100644
--- a/tools/aconfig/aconfig/src/storage/mod.rs
+++ b/tools/aconfig/aconfig/src/storage/mod.rs
@@ -18,7 +18,7 @@
 pub mod flag_value;
 pub mod package_table;
 
-use anyhow::Result;
+use anyhow::{anyhow, Result};
 use std::collections::{HashMap, HashSet};
 
 use crate::storage::{
@@ -107,6 +107,7 @@
             let flag_value = create_flag_value(container, &packages)?;
             Ok(flag_value.as_bytes())
         }
+        _ => Err(anyhow!("aconfig does not support the creation of this storage file type")),
     }
 }
 
diff --git a/tools/aconfig/aconfig/src/storage/package_table.rs b/tools/aconfig/aconfig/src/storage/package_table.rs
index bc2da4d..ca0dec3 100644
--- a/tools/aconfig/aconfig/src/storage/package_table.rs
+++ b/tools/aconfig/aconfig/src/storage/package_table.rs
@@ -17,7 +17,8 @@
 use anyhow::Result;
 
 use aconfig_storage_file::{
-    get_table_size, PackageTable, PackageTableHeader, PackageTableNode, FILE_VERSION, StorageFileType
+    get_table_size, PackageTable, PackageTableHeader, PackageTableNode, StorageFileType,
+    FILE_VERSION,
 };
 
 use crate::storage::FlagPackage;
diff --git a/tools/aconfig/aconfig_storage_file/src/flag_info.rs b/tools/aconfig/aconfig_storage_file/src/flag_info.rs
new file mode 100644
index 0000000..6ece543
--- /dev/null
+++ b/tools/aconfig/aconfig_storage_file/src/flag_info.rs
@@ -0,0 +1,238 @@
+/*
+ * Copyright (C) 2024 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.
+ */
+
+//! flag info module defines the flag info file format and methods for serialization
+//! and deserialization
+
+use crate::{read_str_from_bytes, read_u32_from_bytes, read_u8_from_bytes};
+use crate::{AconfigStorageError, StorageFileType};
+use anyhow::anyhow;
+use std::fmt;
+
+/// Flag info header struct
+#[derive(PartialEq)]
+pub struct FlagInfoHeader {
+    pub version: u32,
+    pub container: String,
+    pub file_type: u8,
+    pub file_size: u32,
+    pub num_flags: u32,
+    pub boolean_flag_offset: u32,
+}
+
+/// Implement debug print trait for header
+impl fmt::Debug for FlagInfoHeader {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(
+            f,
+            "Version: {}, Container: {}, File Type: {:?}, File Size: {}",
+            self.version,
+            self.container,
+            StorageFileType::try_from(self.file_type),
+            self.file_size
+        )?;
+        writeln!(
+            f,
+            "Num of Flags: {}, Boolean Flag Offset:{}",
+            self.num_flags, self.boolean_flag_offset
+        )?;
+        Ok(())
+    }
+}
+
+impl FlagInfoHeader {
+    /// Serialize to bytes
+    pub fn as_bytes(&self) -> Vec<u8> {
+        let mut result = Vec::new();
+        result.extend_from_slice(&self.version.to_le_bytes());
+        let container_bytes = self.container.as_bytes();
+        result.extend_from_slice(&(container_bytes.len() as u32).to_le_bytes());
+        result.extend_from_slice(container_bytes);
+        result.extend_from_slice(&self.file_type.to_le_bytes());
+        result.extend_from_slice(&self.file_size.to_le_bytes());
+        result.extend_from_slice(&self.num_flags.to_le_bytes());
+        result.extend_from_slice(&self.boolean_flag_offset.to_le_bytes());
+        result
+    }
+
+    /// Deserialize from bytes
+    pub fn from_bytes(bytes: &[u8]) -> Result<Self, AconfigStorageError> {
+        let mut head = 0;
+        let list = Self {
+            version: read_u32_from_bytes(bytes, &mut head)?,
+            container: read_str_from_bytes(bytes, &mut head)?,
+            file_type: read_u8_from_bytes(bytes, &mut head)?,
+            file_size: read_u32_from_bytes(bytes, &mut head)?,
+            num_flags: read_u32_from_bytes(bytes, &mut head)?,
+            boolean_flag_offset: read_u32_from_bytes(bytes, &mut head)?,
+        };
+        if list.file_type != StorageFileType::FlagInfo as u8 {
+            return Err(AconfigStorageError::BytesParseFail(anyhow!(
+                "binary file is not a flag info file"
+            )));
+        }
+        Ok(list)
+    }
+}
+
+/// bit field for flag info
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum FlagInfoBit {
+    IsSticky = 0,
+    IsReadWrite = 1,
+    HasOverride = 2,
+}
+
+/// Flag info node struct
+#[derive(PartialEq, Clone)]
+pub struct FlagInfoNode {
+    pub attributes: u8,
+}
+
+/// Implement debug print trait for node
+impl fmt::Debug for FlagInfoNode {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(
+            f,
+            "sticky: {}, readwrite: {}, override: {}",
+            self.attributes & (FlagInfoBit::IsSticky as u8),
+            self.attributes & (FlagInfoBit::IsReadWrite as u8),
+            self.attributes & (FlagInfoBit::HasOverride as u8),
+        )?;
+        Ok(())
+    }
+}
+
+impl FlagInfoNode {
+    /// Serialize to bytes
+    pub fn as_bytes(&self) -> Vec<u8> {
+        let mut result = Vec::new();
+        result.extend_from_slice(&self.attributes.to_le_bytes());
+        result
+    }
+
+    /// Deserialize from bytes
+    pub fn from_bytes(bytes: &[u8]) -> Result<Self, AconfigStorageError> {
+        let mut head = 0;
+        let node = Self { attributes: read_u8_from_bytes(bytes, &mut head)? };
+        Ok(node)
+    }
+}
+
+/// Flag info list struct
+#[derive(PartialEq)]
+pub struct FlagInfoList {
+    pub header: FlagInfoHeader,
+    pub nodes: Vec<FlagInfoNode>,
+}
+
+/// Implement debug print trait for flag info list
+impl fmt::Debug for FlagInfoList {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln!(f, "Header:")?;
+        write!(f, "{:?}", self.header)?;
+        writeln!(f, "Nodes:")?;
+        for node in self.nodes.iter() {
+            write!(f, "{:?}", node)?;
+        }
+        Ok(())
+    }
+}
+
+impl FlagInfoList {
+    /// Serialize to bytes
+    pub fn as_bytes(&self) -> Vec<u8> {
+        [
+            self.header.as_bytes(),
+            self.nodes.iter().map(|v| v.as_bytes()).collect::<Vec<_>>().concat(),
+        ]
+        .concat()
+    }
+
+    /// Deserialize from bytes
+    pub fn from_bytes(bytes: &[u8]) -> Result<Self, AconfigStorageError> {
+        let header = FlagInfoHeader::from_bytes(bytes)?;
+        let num_flags = header.num_flags;
+        let mut head = header.as_bytes().len();
+        let nodes = (0..num_flags)
+            .map(|_| {
+                let node = FlagInfoNode::from_bytes(&bytes[head..])?;
+                head += node.as_bytes().len();
+                Ok(node)
+            })
+            .collect::<Result<Vec<_>, AconfigStorageError>>()
+            .map_err(|errmsg| {
+                AconfigStorageError::BytesParseFail(anyhow!(
+                    "fail to parse flag info list: {}",
+                    errmsg
+                ))
+            })?;
+        let list = Self { header, nodes };
+        Ok(list)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::test_utils::create_test_flag_info_list;
+
+    #[test]
+    // this test point locks down the value list serialization
+    fn test_serialization() {
+        let flag_info_list = create_test_flag_info_list();
+
+        let header: &FlagInfoHeader = &flag_info_list.header;
+        let reinterpreted_header = FlagInfoHeader::from_bytes(&header.as_bytes());
+        assert!(reinterpreted_header.is_ok());
+        assert_eq!(header, &reinterpreted_header.unwrap());
+
+        let nodes: &Vec<FlagInfoNode> = &flag_info_list.nodes;
+        for node in nodes.iter() {
+            let reinterpreted_node = FlagInfoNode::from_bytes(&node.as_bytes()).unwrap();
+            assert_eq!(node, &reinterpreted_node);
+        }
+
+        let flag_info_bytes = flag_info_list.as_bytes();
+        let reinterpreted_info_list = FlagInfoList::from_bytes(&flag_info_bytes);
+        assert!(reinterpreted_info_list.is_ok());
+        assert_eq!(&flag_info_list, &reinterpreted_info_list.unwrap());
+        assert_eq!(flag_info_bytes.len() as u32, header.file_size);
+    }
+
+    #[test]
+    // this test point locks down that version number should be at the top of serialized
+    // bytes
+    fn test_version_number() {
+        let flag_info_list = create_test_flag_info_list();
+        let bytes = &flag_info_list.as_bytes();
+        let mut head = 0;
+        let version = read_u32_from_bytes(bytes, &mut head).unwrap();
+        assert_eq!(version, 1234)
+    }
+
+    #[test]
+    // this test point locks down file type check
+    fn test_file_type_check() {
+        let mut flag_info_list = create_test_flag_info_list();
+        flag_info_list.header.file_type = 123u8;
+        let error = FlagInfoList::from_bytes(&flag_info_list.as_bytes()).unwrap_err();
+        assert_eq!(
+            format!("{:?}", error),
+            format!("BytesParseFail(binary file is not a flag info file)")
+        );
+    }
+}
diff --git a/tools/aconfig/aconfig_storage_file/src/lib.rs b/tools/aconfig/aconfig_storage_file/src/lib.rs
index 24b16a1..50ac69d 100644
--- a/tools/aconfig/aconfig_storage_file/src/lib.rs
+++ b/tools/aconfig/aconfig_storage_file/src/lib.rs
@@ -32,6 +32,7 @@
 //! apis. DO NOT DIRECTLY USE THESE APIS IN YOUR SOURCE CODE. For auto generated flag apis
 //! please refer to the g3doc go/android-flags
 
+pub mod flag_info;
 pub mod flag_table;
 pub mod flag_value;
 pub mod package_table;
@@ -46,6 +47,7 @@
 use std::hash::{Hash, Hasher};
 use std::io::Read;
 
+pub use crate::flag_info::{FlagInfoHeader, FlagInfoList, FlagInfoNode};
 pub use crate::flag_table::{FlagTable, FlagTableHeader, FlagTableNode};
 pub use crate::flag_value::{FlagValueHeader, FlagValueList};
 pub use crate::package_table::{PackageTable, PackageTableHeader, PackageTableNode};
@@ -68,6 +70,7 @@
     PackageMap = 0,
     FlagMap = 1,
     FlagVal = 2,
+    FlagInfo = 3,
 }
 
 impl TryFrom<&str> for StorageFileType {
@@ -78,6 +81,7 @@
             "package_map" => Ok(Self::PackageMap),
             "flag_map" => Ok(Self::FlagMap),
             "flag_val" => Ok(Self::FlagVal),
+            "flag_info" => Ok(Self::FlagInfo),
             _ => Err(anyhow!(
                 "Invalid storage file type, valid types are package_map|flag_map|flag_val"
             )),
@@ -93,6 +97,7 @@
             x if x == Self::PackageMap as u8 => Ok(Self::PackageMap),
             x if x == Self::FlagMap as u8 => Ok(Self::FlagMap),
             x if x == Self::FlagVal as u8 => Ok(Self::FlagVal),
+            x if x == Self::FlagInfo as u8 => Ok(Self::FlagInfo),
             _ => Err(anyhow!("Invalid storage file type")),
         }
     }
@@ -219,7 +224,7 @@
     package_map: &str,
     flag_map: &str,
     flag_val: &str,
-) -> Result<Vec<(String, bool)>, AconfigStorageError> {
+) -> Result<Vec<(String, String, bool)>, AconfigStorageError> {
     let package_table = PackageTable::from_bytes(&read_file_to_bytes(package_map)?)?;
     let flag_table = FlagTable::from_bytes(&read_file_to_bytes(flag_map)?)?;
     let flag_value_list = FlagValueList::from_bytes(&read_file_to_bytes(flag_val)?)?;
@@ -232,10 +237,9 @@
     let mut flags = Vec::new();
     for node in flag_table.nodes.iter() {
         let (package_name, package_offset) = package_info[node.package_id as usize];
-        let full_flag_name = String::from(package_name) + "/" + &node.flag_name;
         let flag_offset = package_offset + node.flag_id as u32;
         let flag_value = flag_value_list.booleans[flag_offset as usize];
-        flags.push((full_flag_name, flag_value));
+        flags.push((String::from(package_name), node.flag_name.clone(), flag_value));
     }
 
     flags.sort_by(|v1, v2| v1.0.cmp(&v2.0));
@@ -266,14 +270,30 @@
         let flags =
             list_flags(&package_table_path, &flag_table_path, &flag_value_list_path).unwrap();
         let expected = [
-            (String::from("com.android.aconfig.storage.test_1/disabled_rw"), false),
-            (String::from("com.android.aconfig.storage.test_1/enabled_ro"), true),
-            (String::from("com.android.aconfig.storage.test_1/enabled_rw"), false),
-            (String::from("com.android.aconfig.storage.test_2/disabled_ro"), false),
-            (String::from("com.android.aconfig.storage.test_2/enabled_fixed_ro"), true),
-            (String::from("com.android.aconfig.storage.test_2/enabled_ro"), true),
-            (String::from("com.android.aconfig.storage.test_4/enabled_fixed_ro"), false),
-            (String::from("com.android.aconfig.storage.test_4/enabled_ro"), true),
+            (String::from("com.android.aconfig.storage.test_1"), String::from("enabled_ro"), true),
+            (String::from("com.android.aconfig.storage.test_1"), String::from("enabled_rw"), false),
+            (
+                String::from("com.android.aconfig.storage.test_1"),
+                String::from("disabled_rw"),
+                false,
+            ),
+            (
+                String::from("com.android.aconfig.storage.test_2"),
+                String::from("disabled_ro"),
+                false,
+            ),
+            (
+                String::from("com.android.aconfig.storage.test_2"),
+                String::from("enabled_fixed_ro"),
+                true,
+            ),
+            (String::from("com.android.aconfig.storage.test_2"), String::from("enabled_ro"), true),
+            (String::from("com.android.aconfig.storage.test_4"), String::from("enabled_ro"), true),
+            (
+                String::from("com.android.aconfig.storage.test_4"),
+                String::from("enabled_fixed_ro"),
+                false,
+            ),
         ];
         assert_eq!(flags, expected);
     }
diff --git a/tools/aconfig/aconfig_storage_file/src/main.rs b/tools/aconfig/aconfig_storage_file/src/main.rs
index 293d018..12e0024 100644
--- a/tools/aconfig/aconfig_storage_file/src/main.rs
+++ b/tools/aconfig/aconfig_storage_file/src/main.rs
@@ -17,8 +17,8 @@
 //! `aconfig-storage` is a debugging tool to parse storage files
 
 use aconfig_storage_file::{
-    list_flags, read_file_to_bytes, AconfigStorageError, FlagTable, FlagValueList, PackageTable,
-    StorageFileType,
+    list_flags, read_file_to_bytes, AconfigStorageError, FlagInfoList, FlagTable, FlagValueList,
+    PackageTable, StorageFileType,
 };
 
 use clap::{builder::ArgAction, Arg, Command};
@@ -67,6 +67,10 @@
             let flag_value = FlagValueList::from_bytes(&bytes)?;
             println!("{:?}", flag_value);
         }
+        StorageFileType::FlagInfo => {
+            let flag_info = FlagInfoList::from_bytes(&bytes)?;
+            println!("{:?}", flag_info);
+        }
     }
     Ok(())
 }
diff --git a/tools/aconfig/aconfig_storage_file/src/test_utils.rs b/tools/aconfig/aconfig_storage_file/src/test_utils.rs
index 586bb4c..4641829 100644
--- a/tools/aconfig/aconfig_storage_file/src/test_utils.rs
+++ b/tools/aconfig/aconfig_storage_file/src/test_utils.rs
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+use crate::flag_info::{FlagInfoHeader, FlagInfoList, FlagInfoNode};
 use crate::flag_table::{FlagTable, FlagTableHeader, FlagTableNode};
 use crate::flag_value::{FlagValueHeader, FlagValueList};
 use crate::package_table::{PackageTable, PackageTableHeader, PackageTableNode};
@@ -124,6 +125,19 @@
     FlagValueList { header, booleans }
 }
 
+pub(crate) fn create_test_flag_info_list() -> FlagInfoList {
+    let header = FlagInfoHeader {
+        version: 1234,
+        container: String::from("system"),
+        file_type: StorageFileType::FlagInfo as u8,
+        file_size: 35,
+        num_flags: 8,
+        boolean_flag_offset: 27,
+    };
+    let nodes: Vec<FlagInfoNode> = vec![FlagInfoNode { attributes: 0 }; 8];
+    FlagInfoList { header, nodes }
+}
+
 pub(crate) fn write_bytes_to_temp_file(bytes: &[u8]) -> Result<NamedTempFile, AconfigStorageError> {
     let mut file = NamedTempFile::new().map_err(|_| {
         AconfigStorageError::FileCreationFail(anyhow!("Failed to create temp file"))
diff --git a/tools/aconfig/aconfig_storage_read_api/aconfig_storage_read_api.cpp b/tools/aconfig/aconfig_storage_read_api/aconfig_storage_read_api.cpp
index ea756b3..2213831 100644
--- a/tools/aconfig/aconfig_storage_read_api/aconfig_storage_read_api.cpp
+++ b/tools/aconfig/aconfig_storage_read_api/aconfig_storage_read_api.cpp
@@ -67,18 +67,18 @@
 static Result<MappedStorageFile> map_storage_file(std::string const& file) {
   int fd = open(file.c_str(), O_CLOEXEC | O_NOFOLLOW | O_RDONLY);
   if (fd == -1) {
-    return Error() << "failed to open " << file;
+    return ErrnoError() << "failed to open " << file;
   };
 
   struct stat fd_stat;
   if (fstat(fd, &fd_stat) < 0) {
-    return Error() << "fstat failed";
+    return ErrnoError() << "fstat failed";
   }
   size_t file_size = fd_stat.st_size;
 
   void* const map_result = mmap(nullptr, file_size, PROT_READ, MAP_SHARED, fd, 0);
   if (map_result == MAP_FAILED) {
-    return Error() << "mmap failed";
+    return ErrnoError() << "mmap failed";
   }
 
   auto mapped_file = MappedStorageFile();
diff --git a/tools/aconfig/aconfig_storage_read_api/src/mapped_file.rs b/tools/aconfig/aconfig_storage_read_api/src/mapped_file.rs
index 86c6a1b..51354db 100644
--- a/tools/aconfig/aconfig_storage_read_api/src/mapped_file.rs
+++ b/tools/aconfig/aconfig_storage_read_api/src/mapped_file.rs
@@ -91,6 +91,9 @@
         StorageFileType::PackageMap => unsafe { map_file(files_location.package_map()) },
         StorageFileType::FlagMap => unsafe { map_file(files_location.flag_map()) },
         StorageFileType::FlagVal => unsafe { map_file(files_location.flag_val()) },
+        StorageFileType::FlagInfo => {
+            Err(MapFileFail(anyhow!("TODO: add support for flag info file")))
+        }
     }
 }
 
diff --git a/tools/aconfig/aconfig_storage_write_api/aconfig_storage_write_api.cpp b/tools/aconfig/aconfig_storage_write_api/aconfig_storage_write_api.cpp
index 391b305..e863c0e 100644
--- a/tools/aconfig/aconfig_storage_write_api/aconfig_storage_write_api.cpp
+++ b/tools/aconfig/aconfig_storage_write_api/aconfig_storage_write_api.cpp
@@ -58,24 +58,24 @@
 static Result<MappedFlagValueFile> map_storage_file(std::string const& file) {
   struct stat file_stat;
   if (stat(file.c_str(), &file_stat) < 0) {
-    return Error() << "fstat failed";
+    return ErrnoError() << "stat failed";
   }
 
   if ((file_stat.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) == 0) {
-    return Error() << "cannot map nonwriteable file";
+    return ErrnoError() << "cannot map nonwriteable file";
   }
 
   size_t file_size = file_stat.st_size;
 
   const int fd = open(file.c_str(), O_RDWR | O_NOFOLLOW | O_CLOEXEC);
   if (fd == -1) {
-    return Error() << "failed to open " << file;
+    return ErrnoError() << "failed to open " << file;
   };
 
   void* const map_result =
       mmap(nullptr, file_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
   if (map_result == MAP_FAILED) {
-    return Error() << "mmap failed";
+    return ErrnoError() << "mmap failed";
   }
 
   auto mapped_file = MappedFlagValueFile();
@@ -95,7 +95,12 @@
   if (!file_result.ok()) {
     return Error() << file_result.error();
   }
-  return map_storage_file(*file_result);
+  auto mapped_result = map_storage_file(*file_result);
+  if (!mapped_result.ok()) {
+    return Error() << "failed to map " << *file_result << ": "
+                   << mapped_result.error();
+  }
+  return *mapped_result;
 }
 
 } // namespace private internal api
diff --git a/tools/aconfig/aflags/Android.bp b/tools/aconfig/aflags/Android.bp
index b36aa34..4920a6f 100644
--- a/tools/aconfig/aflags/Android.bp
+++ b/tools/aconfig/aflags/Android.bp
@@ -10,6 +10,8 @@
     srcs: ["src/main.rs"],
     rustlibs: [
         "libaconfig_protos",
+        "libaconfig_storage_read_api",
+        "libaconfig_storage_file",
         "libanyhow",
         "libclap",
         "libnix",
diff --git a/tools/aconfig/aflags/Cargo.toml b/tools/aconfig/aflags/Cargo.toml
index 6a08da6..cce7f9d 100644
--- a/tools/aconfig/aflags/Cargo.toml
+++ b/tools/aconfig/aflags/Cargo.toml
@@ -6,8 +6,10 @@
 [dependencies]
 anyhow = "1.0.69"
 paste = "1.0.11"
-clap = { version = "4", features = ["derive"] }
 protobuf = "3.2.0"
 regex = "1.10.3"
 aconfig_protos = { path = "../aconfig_protos" }
 nix = { version = "0.28.0", features = ["user"] }
+aconfig_storage_file = { version = "0.1.0", path = "../aconfig_storage_file" }
+aconfig_storage_read_api = { version = "0.1.0", path = "../aconfig_storage_read_api" }
+clap = {version = "4.5.2" }
diff --git a/tools/aconfig/aflags/src/aconfig_storage_source.rs b/tools/aconfig/aflags/src/aconfig_storage_source.rs
new file mode 100644
index 0000000..1d73688
--- /dev/null
+++ b/tools/aconfig/aflags/src/aconfig_storage_source.rs
@@ -0,0 +1,56 @@
+use crate::{Flag, FlagPermission, FlagSource, FlagValue, ValuePickedFrom};
+use anyhow::{anyhow, Result};
+
+use std::fs::File;
+use std::io::Read;
+
+pub struct AconfigStorageSource {}
+
+use aconfig_storage_file::protos::ProtoStorageFiles;
+
+static STORAGE_INFO_FILE_PATH: &str = "/metadata/aconfig/persistent_storage_file_records.pb";
+
+impl FlagSource for AconfigStorageSource {
+    fn list_flags() -> Result<Vec<Flag>> {
+        let mut result = Vec::new();
+
+        let mut file = File::open(STORAGE_INFO_FILE_PATH)?;
+        let mut bytes = Vec::new();
+        file.read_to_end(&mut bytes)?;
+        let storage_file_info: ProtoStorageFiles = protobuf::Message::parse_from_bytes(&bytes)?;
+
+        for file_info in storage_file_info.files {
+            let package_map =
+                file_info.package_map.ok_or(anyhow!("storage file is missing package map"))?;
+            let flag_map = file_info.flag_map.ok_or(anyhow!("storage file is missing flag map"))?;
+            let flag_val = file_info.flag_val.ok_or(anyhow!("storage file is missing flag val"))?;
+            let container =
+                file_info.container.ok_or(anyhow!("storage file is missing container"))?;
+
+            for (package, name, val) in
+                aconfig_storage_file::list_flags(&package_map, &flag_map, &flag_val)?
+            {
+                result.push(Flag {
+                    name: name.to_string(),
+                    package: package.to_string(),
+                    value: FlagValue::try_from(val.to_string().as_str())?,
+                    container: container.to_string(),
+
+                    // TODO(b/324436145): delete namespace field once DeviceConfig isn't in CLI.
+                    namespace: "-".to_string(),
+
+                    // TODO(b/324436145): Populate with real values once API is available.
+                    staged_value: None,
+                    permission: FlagPermission::ReadOnly,
+                    value_picked_from: ValuePickedFrom::Default,
+                });
+            }
+        }
+
+        Ok(result)
+    }
+
+    fn override_flag(_namespace: &str, _qualified_name: &str, _value: &str) -> Result<()> {
+        todo!()
+    }
+}
diff --git a/tools/aconfig/aflags/src/main.rs b/tools/aconfig/aflags/src/main.rs
index 808ffa0..1c453c5 100644
--- a/tools/aconfig/aflags/src/main.rs
+++ b/tools/aconfig/aflags/src/main.rs
@@ -22,6 +22,9 @@
 mod device_config_source;
 use device_config_source::DeviceConfigSource;
 
+mod aconfig_storage_source;
+use aconfig_storage_source::AconfigStorageSource;
+
 #[derive(Clone, PartialEq, Debug)]
 enum FlagPermission {
     ReadOnly,
@@ -109,6 +112,11 @@
     fn override_flag(namespace: &str, qualified_name: &str, value: &str) -> Result<()>;
 }
 
+enum FlagSourceType {
+    DeviceConfig,
+    AconfigStorage,
+}
+
 const ABOUT_TEXT: &str = "Tool for reading and writing flags.
 
 Rows in the table from the `list` command follow this format:
@@ -139,7 +147,11 @@
 #[derive(Parser, Debug)]
 enum Command {
     /// List all aconfig flags on this device.
-    List,
+    List {
+        /// Read from the new flag storage.
+        #[clap(long)]
+        use_new_storage: bool,
+    },
 
     /// Enable an aconfig flag on this device, on the next boot.
     Enable {
@@ -201,8 +213,11 @@
     Ok(())
 }
 
-fn list() -> Result<String> {
-    let flags = DeviceConfigSource::list_flags()?;
+fn list(source_type: FlagSourceType) -> Result<String> {
+    let flags = match source_type {
+        FlagSourceType::DeviceConfig => DeviceConfigSource::list_flags()?,
+        FlagSourceType::AconfigStorage => AconfigStorageSource::list_flags()?,
+    };
     let padding_info = PaddingInfo {
         longest_flag_col: flags.iter().map(|f| f.qualified_name().len()).max().unwrap_or(0),
         longest_val_col: flags.iter().map(|f| f.value.to_string().len()).max().unwrap_or(0),
@@ -234,7 +249,8 @@
 fn main() {
     let cli = Cli::parse();
     let output = match cli.command {
-        Command::List => list().map(Some),
+        Command::List { use_new_storage: true } => list(FlagSourceType::AconfigStorage).map(Some),
+        Command::List { use_new_storage: false } => list(FlagSourceType::DeviceConfig).map(Some),
         Command::Enable { qualified_name } => set_flag(&qualified_name, "true").map(|_| None),
         Command::Disable { qualified_name } => set_flag(&qualified_name, "false").map(|_| None),
     };