From cf8f042a2052037b698ec39f9b18c5123a6235a4 Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Fri, 13 Aug 2021 04:53:11 -0700
Subject: [PATCH] Cleanup magiskboot cpio code

---
 native/jni/Android.mk                     |  2 +-
 native/jni/external/Android.mk            |  3 +-
 native/jni/{utils => magiskboot}/cpio.cpp | 84 ++++++++++-------------
 native/jni/magiskboot/cpio.hpp            | 55 +++++++++++++++
 native/jni/magiskboot/ramdisk.cpp         | 67 +++++++++---------
 native/jni/utils/include/cpio.hpp         | 68 ------------------
 6 files changed, 127 insertions(+), 152 deletions(-)
 rename native/jni/{utils => magiskboot}/cpio.cpp (72%)
 create mode 100644 native/jni/magiskboot/cpio.hpp
 delete mode 100644 native/jni/utils/include/cpio.hpp

diff --git a/native/jni/Android.mk b/native/jni/Android.mk
index 5daeb4512..93d06b0aa 100644
--- a/native/jni/Android.mk
+++ b/native/jni/Android.mk
@@ -97,7 +97,7 @@ LOCAL_SRC_FILES := \
     magiskboot/dtb.cpp \
     magiskboot/ramdisk.cpp \
     magiskboot/pattern.cpp \
-    utils/cpio.cpp
+    magiskboot/cpio.cpp
 
 LOCAL_LDFLAGS := -static
 include $(BUILD_EXECUTABLE)
diff --git a/native/jni/external/Android.mk b/native/jni/external/Android.mk
index 4dab7ee39..34985d154 100644
--- a/native/jni/external/Android.mk
+++ b/native/jni/external/Android.mk
@@ -3,8 +3,7 @@ LOCAL_PATH := $(call my-dir)
 # Header only library
 include $(CLEAR_VARS)
 LOCAL_MODULE:= libphmap
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/parallel-hashmap
-LOCAL_EXPORT_C_INCLUDES := $(LOCAL_C_INCLUDES)
+LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/parallel-hashmap
 include $(BUILD_STATIC_LIBRARY)
 
 # libxz.a
diff --git a/native/jni/utils/cpio.cpp b/native/jni/magiskboot/cpio.cpp
similarity index 72%
rename from native/jni/utils/cpio.cpp
rename to native/jni/magiskboot/cpio.cpp
index 673df1b02..d71fbf8c5 100644
--- a/native/jni/utils/cpio.cpp
+++ b/native/jni/magiskboot/cpio.cpp
@@ -1,11 +1,10 @@
 #include <unistd.h>
 #include <fcntl.h>
-#include <string.h>
-#include <stdlib.h>
 #include <algorithm>
 
 #include <utils.hpp>
-#include <cpio.hpp>
+
+#include "cpio.hpp"
 
 using namespace std;
 
@@ -43,8 +42,11 @@ static uint32_t x8u(const char *hex) {
     return val;
 }
 
-cpio_entry_base::cpio_entry_base(const cpio_newc_header *h)
-: mode(x8u(h->mode)), uid(x8u(h->uid)), gid(x8u(h->gid)), filesize(x8u(h->filesize)) {};
+cpio_entry::cpio_entry(uint32_t mode) : mode(mode), uid(0), gid(0), filesize(0), data(nullptr) {}
+
+cpio_entry::cpio_entry(const cpio_newc_header *h) :
+mode(x8u(h->mode)), uid(x8u(h->uid)), gid(x8u(h->gid)), filesize(x8u(h->filesize)), data(nullptr)
+{}
 
 void cpio::dump(const char *file) {
     fprintf(stderr, "Dump cpio: [%s]\n", file);
@@ -71,12 +73,12 @@ void cpio::rm(const char *name, bool r) {
     }
 }
 
-static void extract_entry(const entry_map::value_type &e, const char *file) {
+void cpio::extract_entry(const entry_map::value_type &e, const char *file) {
     fprintf(stderr, "Extract [%s] to [%s]\n", e.first.data(), file);
     unlink(file);
     rmdir(file);
     if (S_ISDIR(e.second->mode)) {
-        mkdir(file, e.second->mode & 0777);
+        ::mkdir(file, e.second->mode & 0777);
     } else if (S_ISREG(e.second->mode)) {
         int fd = creat(file, e.second->mode & 0777);
         xwrite(fd, e.second->data, e.second->filesize);
@@ -148,11 +150,7 @@ void cpio::dump(FILE *out) {
     fclose(out);
 }
 
-cpio_rw::cpio_rw(const char *file) {
-    load_cpio(file);
-}
-
-void cpio_rw::load_cpio(const char *file) {
+void cpio::load_cpio(const char *file) {
     char *buf;
     size_t sz;
     mmap_ro(file, buf, sz);
@@ -161,54 +159,49 @@ void cpio_rw::load_cpio(const char *file) {
     munmap(buf, sz);
 }
 
-void cpio_rw::insert(cpio_entry *e) {
-    auto ex = entries.extract(e->filename);
-    if (!ex) {
-        entries[e->filename].reset(e);
+void cpio::insert(string_view name, cpio_entry *e) {
+    auto it = entries.find(name);
+    if (it != entries.end()) {
+        it->second.reset(e);
     } else {
-        ex.key() = e->filename;
-        ex.mapped().reset(e);
-        entries.insert(std::move(ex));
+        entries.emplace(name, e);
     }
 }
 
-void cpio_rw::add(mode_t mode, const char *name, const char *file) {
+void cpio::add(mode_t mode, const char *name, const char *file) {
     void *buf;
     size_t sz;
     mmap_ro(file, buf, sz);
-    auto e = new cpio_entry(name, S_IFREG | mode);
+    auto e = new cpio_entry(S_IFREG | mode);
     e->filesize = sz;
     e->data = xmalloc(sz);
     memcpy(e->data, buf, sz);
     munmap(buf, sz);
-    insert(e);
+    insert(name, e);
     fprintf(stderr, "Add entry [%s] (%04o)\n", name, mode);
 }
 
-void cpio_rw::mkdir(mode_t mode, const char *name) {
-    insert(new cpio_entry(name, S_IFDIR | mode));
+void cpio::mkdir(mode_t mode, const char *name) {
+    insert(name, new cpio_entry(S_IFDIR | mode));
     fprintf(stderr, "Create directory [%s] (%04o)\n", name, mode);
 }
 
-void cpio_rw::ln(const char *target, const char *name) {
-    auto e = new cpio_entry(name, S_IFLNK);
+void cpio::ln(const char *target, const char *name) {
+    auto e = new cpio_entry(S_IFLNK);
     e->filesize = strlen(target);
     e->data = strdup(target);
-    insert(e);
+    insert(name, e);
     fprintf(stderr, "Create symlink [%s] -> [%s]\n", name, target);
 }
 
-void cpio_rw::mv(entry_map::iterator &it, const char *to) {
-    fprintf(stderr, "Move [%s] -> [%s]\n", it->first.data(), to);
-    auto ex = entries.extract(it);
-    auto &name = static_cast<cpio_entry*>(ex.mapped().get())->filename;
-    name = to;
-    ex.key() = name;
-    entries.erase(name);
-    entries.insert(std::move(ex));
+void cpio::mv(entry_map::iterator &it, const char *name) {
+    fprintf(stderr, "Move [%s] -> [%s]\n", it->first.data(), name);
+    auto e = it->second.release();
+    entries.erase(it);
+    insert(name, e);
 }
 
-bool cpio_rw::mv(const char *from, const char *to) {
+bool cpio::mv(const char *from, const char *to) {
     auto it = entries.find(from);
     if (it != entries.end()) {
         mv(it, to);
@@ -220,26 +213,23 @@ bool cpio_rw::mv(const char *from, const char *to) {
 
 #define pos_align(p) p = do_align(p, 4)
 
-void cpio_rw::load_cpio(const char *buf, size_t sz) {
+void cpio::load_cpio(const char *buf, size_t sz) {
     size_t pos = 0;
-    const cpio_newc_header *header;
-    unique_ptr<cpio_entry> entry;
     while (pos < sz) {
-        header = reinterpret_cast<const cpio_newc_header *>(buf + pos);
-        entry = make_unique<cpio_entry>(header);
-        pos += sizeof(*header);
-        string_view name_view(buf + pos);
+        auto header = reinterpret_cast<const cpio_newc_header *>(buf + pos);
+        pos += sizeof(cpio_newc_header);
+        string_view name(buf + pos);
         pos += x8u(header->namesize);
         pos_align(pos);
-        if (name_view == "." || name_view == "..")
+        if (name == "." || name == "..")
             continue;
-        if (name_view == "TRAILER!!!")
+        if (name == "TRAILER!!!")
             break;
-        entry->filename = name_view;
+        auto entry = new cpio_entry(header);
         entry->data = xmalloc(entry->filesize);
         memcpy(entry->data, buf + pos, entry->filesize);
         pos += entry->filesize;
-        entries[entry->filename] = std::move(entry);
+        insert(name, entry);
         pos_align(pos);
     }
 }
diff --git a/native/jni/magiskboot/cpio.hpp b/native/jni/magiskboot/cpio.hpp
new file mode 100644
index 000000000..8a1b9ab64
--- /dev/null
+++ b/native/jni/magiskboot/cpio.hpp
@@ -0,0 +1,55 @@
+#pragma once
+
+#include <stdint.h>
+#include <string>
+#include <memory>
+#include <map>
+#include <string_view>
+
+struct cpio_newc_header;
+
+struct cpio_entry {
+    uint32_t mode;
+    uint32_t uid;
+    uint32_t gid;
+    uint32_t filesize;
+    void *data;
+
+    explicit cpio_entry(uint32_t mode = 0);
+    explicit cpio_entry(const cpio_newc_header *h);
+    ~cpio_entry() { free(data); }
+};
+
+class cpio {
+public:
+    struct StringCmp {
+        using is_transparent = void;
+        bool operator()(std::string_view a, std::string_view b) const {
+            return a < b;
+        }
+    };
+    using entry_map = std::map<std::string, std::unique_ptr<cpio_entry>, StringCmp>;
+
+    void load_cpio(const char *file);
+    void dump(const char *file);
+    void rm(const char *name, bool r = false);
+    void extract();
+    bool extract(const char *name, const char *file);
+    bool exists(const char *name);
+    void add(mode_t mode, const char *name, const char *file);
+    void mkdir(mode_t mode, const char *name);
+    void ln(const char *target, const char *name);
+    bool mv(const char *from, const char *to);
+
+protected:
+    entry_map entries;
+
+    static void extract_entry(const entry_map::value_type &e, const char *file);
+    void rm(entry_map::iterator &it);
+    void mv(entry_map::iterator &it, const char *name);
+
+private:
+    void dump(FILE *out);
+    void insert(std::string_view name, cpio_entry *e);
+    void load_cpio(const char *buf, size_t sz);
+};
diff --git a/native/jni/magiskboot/ramdisk.cpp b/native/jni/magiskboot/ramdisk.cpp
index 9e8dd9887..7b928e0af 100644
--- a/native/jni/magiskboot/ramdisk.cpp
+++ b/native/jni/magiskboot/ramdisk.cpp
@@ -1,6 +1,6 @@
 #include <utils.hpp>
-#include <cpio.hpp>
 
+#include "cpio.hpp"
 #include "magiskboot.hpp"
 #include "compress.hpp"
 
@@ -14,9 +14,8 @@ static const char *MAGISK_LIST[] =
         { ".backup/.magisk", "init.magisk.rc",
           "overlay/init.magisk.rc" };
 
-class magisk_cpio : public cpio_rw {
+class magisk_cpio : public cpio {
 public:
-    using cpio_rw::cpio_rw;
     void patch();
     int test();
     char *sha1();
@@ -95,7 +94,7 @@ char *magisk_cpio::sha1() {
             }
         } else if (e.first == ".backup/.magisk") {
             for_each_line(line, e.second->data, e.second->filesize) {
-                if (strncmp(line, "SHA1=", 5) == 0) {
+                if (str_starts(line, "SHA1=")) {
                     strncpy(sha1, line + 5, 40);
                     sha1[40] = '\0';
                     return strdup(sha1);
@@ -114,15 +113,16 @@ for (str = (char *) buf; str < (char *) buf + size; str = str += strlen(str) + 1
 void magisk_cpio::restore() {
     if (auto it = entries.find(".backup/.rmlist"); it != entries.end()) {
         char *file;
-        for_each_str(file, it->second->data, it->second->filesize)
-            rm(file, false);
+        for_each_str(file, it->second->data, it->second->filesize) {
+            rm(file);
+        }
         rm(it);
     }
 
     for (auto it = entries.begin(); it != entries.end();) {
         auto cur = it++;
         if (str_starts(cur->first, ".backup")) {
-            if (cur->first.length() == 7 || cur->first.substr(8) == ".magisk") {
+            if (cur->first.length() == 7 || &cur->first[8] == ".magisk"sv) {
                 rm(cur);
             } else {
                 mv(cur, &cur->first[8]);
@@ -140,15 +140,15 @@ void magisk_cpio::restore() {
 void magisk_cpio::backup(const char *orig) {
     if (access(orig, R_OK))
         return;
-    entry_map bkup_entries;
-    string remv;
 
-    auto b = new cpio_entry(".backup", S_IFDIR);
-    bkup_entries[b->filename].reset(b);
+    entry_map backups;
+    string rm_list;
+    backups.emplace(".backup", new cpio_entry(S_IFDIR));
 
-    magisk_cpio o(orig);
+    magisk_cpio o;
+    o.load_cpio(orig);
 
-    // Remove possible backups in original ramdisk
+    // Remove existing backups in original ramdisk
     o.rm(".backup", true);
     rm(".backup", true);
 
@@ -157,7 +157,7 @@ void magisk_cpio::backup(const char *orig) {
 
     while (lhs != o.entries.end() || rhs != entries.end()) {
         int res;
-        bool backup = false;
+        bool do_backup = false;
         if (lhs != o.entries.end() && rhs != entries.end()) {
             res = lhs->first.compare(rhs->first);
         } else if (lhs == o.entries.end()) {
@@ -167,29 +167,28 @@ void magisk_cpio::backup(const char *orig) {
         }
 
         if (res < 0) {
-            // Something is missing in new ramdisk, backup!
-            backup = true;
+            // Something is missing in new ramdisk, do_backup!
+            do_backup = true;
             fprintf(stderr, "Backup missing entry: ");
         } else if (res == 0) {
             if (lhs->second->filesize != rhs->second->filesize ||
                 memcmp(lhs->second->data, rhs->second->data, lhs->second->filesize) != 0) {
                 // Not the same!
-                backup = true;
+                do_backup = true;
                 fprintf(stderr, "Backup mismatch entry: ");
             }
         } else {
             // Something new in ramdisk
-            remv += rhs->first;
-            remv += (char) '\0';
+            rm_list += rhs->first;
+            rm_list += (char) '\0';
             fprintf(stderr, "Record new entry: [%s] -> [.backup/.rmlist]\n", rhs->first.data());
         }
-        if (backup) {
-            string back_name(".backup/");
-            back_name += lhs->first;
-            fprintf(stderr, "[%s] -> [%s]\n", lhs->first.data(), back_name.data());
-            auto ex = static_cast<cpio_entry*>(lhs->second.release());
-            ex->filename = back_name;
-            bkup_entries[ex->filename].reset(ex);
+
+        if (do_backup) {
+            string name = ".backup/" + lhs->first;
+            fprintf(stderr, "[%s] -> [%s]\n", lhs->first.data(), name.data());
+            auto e = lhs->second.release();
+            backups.emplace(name, e);
         }
 
         // Increment positions
@@ -202,16 +201,16 @@ void magisk_cpio::backup(const char *orig) {
         }
     }
 
-    if (!remv.empty()) {
-        auto rmlist = new cpio_entry(".backup/.rmlist", S_IFREG);
-        rmlist->filesize = remv.length();
-        rmlist->data = xmalloc(remv.length());
-        memcpy(rmlist->data, remv.data(), remv.length());
-        bkup_entries[rmlist->filename].reset(rmlist);
+    if (!rm_list.empty()) {
+        auto rm_list_file = new cpio_entry(S_IFREG);
+        rm_list_file->filesize = rm_list.length();
+        rm_list_file->data = xmalloc(rm_list.length());
+        memcpy(rm_list_file->data, rm_list.data(), rm_list.length());
+        backups.emplace(".backup/.rmlist", rm_list_file);
     }
 
-    if (bkup_entries.size() > 1)
-        entries.merge(bkup_entries);
+    if (backups.size() > 1)
+        entries.merge(backups);
 }
 
 int cpio_commands(int argc, char *argv[]) {
diff --git a/native/jni/utils/include/cpio.hpp b/native/jni/utils/include/cpio.hpp
deleted file mode 100644
index 145a56260..000000000
--- a/native/jni/utils/include/cpio.hpp
+++ /dev/null
@@ -1,68 +0,0 @@
-#pragma once
-
-#include <stdint.h>
-#include <string>
-#include <memory>
-#include <map>
-#include <string_view>
-
-#include <stream.hpp>
-
-struct cpio_newc_header;
-
-struct cpio_entry_base {
-    uint32_t mode = 0;
-    uint32_t uid = 0;
-    uint32_t gid = 0;
-    uint32_t filesize = 0;
-
-    void *data = nullptr;
-
-    cpio_entry_base() : mode(0), uid(0), gid(0), filesize(0) {};
-    explicit cpio_entry_base(const cpio_newc_header *h);
-    virtual ~cpio_entry_base() = default;
-};
-
-struct cpio_entry : public cpio_entry_base {
-    std::string filename;
-
-    cpio_entry() = default;
-    explicit cpio_entry(const char *name, uint32_t mode) : filename(name) {
-        this->mode = mode;
-    }
-    explicit cpio_entry(const cpio_newc_header *h) : cpio_entry_base(h) {}
-
-    ~cpio_entry() override { free(data); };
-};
-
-typedef std::map<std::string_view, std::unique_ptr<cpio_entry_base>> entry_map;
-
-class cpio {
-public:
-    void dump(const char *file);
-    void rm(const char *name, bool r = false);
-    void extract();
-    bool extract(const char *name, const char *file);
-    bool exists(const char *name);
-
-protected:
-    entry_map entries;
-    void rm(entry_map::iterator &it);
-    void dump(FILE *out);
-};
-
-class cpio_rw : public cpio {
-public:
-    cpio_rw() = default;
-    explicit cpio_rw(const char *file);
-    void load_cpio(const char *file);
-    void add(mode_t mode, const char *name, const char *file);
-    void mkdir(mode_t mode, const char *name);
-    void ln(const char *target, const char *name);
-    bool mv(const char *from, const char *to);
-
-protected:
-    void insert(cpio_entry *e);
-    void mv(entry_map::iterator &it, const char *to);
-    void load_cpio(const char *buf, size_t sz);
-};