The name is Zygisk

native/jni/zygisk/utils.cpp

@@ -0,0 +1,100 @@
+#include <cinttypes>
+#include <utils.hpp>
+
+#include "inject.hpp"
+
+using namespace std;
+
+namespace {
+
+struct map_info {
+    uintptr_t start;
+    uintptr_t end;
+    uintptr_t off;
+    int perms;
+    char *path;
+
+    map_info() : start(0), end(0), off(0), perms(0), path(nullptr) {}
+
+    enum {
+        EXEC = (1 << 0),
+        WRITE = (1 << 1),
+        READ = (1 << 2),
+    };
+};
+
+} // namespace
+
+template<typename Func>
+static void parse_maps(int pid, Func fn) {
+    char file[32];
+
+    // format: start-end perms offset dev inode path
+    sprintf(file, "/proc/%d/maps", pid);
+    file_readline(true, file, [=](string_view l) -> bool {
+        char *line = (char *) l.data();
+        map_info info;
+        char perm[5];
+        int path_off;
+
+        if (sscanf(line, "%" PRIxPTR "-%" PRIxPTR " %4s %" PRIxPTR " %*x:%*x %*d %n%*s",
+                   &info.start, &info.end, perm, &info.off, &path_off) != 4)
+            return true;
+
+        // Parse permissions
+        if (perm[0] != '-')
+            info.perms |= map_info::READ;
+        if (perm[1] != '-')
+            info.perms |= map_info::WRITE;
+        if (perm[2] != '-')
+            info.perms |= map_info::EXEC;
+
+        info.path = line + path_off;
+
+        return fn(info);
+    });
+}
+
+void unmap_all(const char *name) {
+    vector<map_info> unmaps;
+    parse_maps(getpid(), [=, &unmaps](map_info &info) -> bool {
+        if (strcmp(info.path, name) == 0)
+            unmaps.emplace_back(info);
+        return true;
+    });
+    for (map_info &info : unmaps) {
+        void *addr = reinterpret_cast<void *>(info.start);
+        size_t size = info.end - info.start;
+        munmap(addr, size);
+        if (info.perms & map_info::READ) {
+            // Make sure readable pages are still readable
+            xmmap(addr, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+        }
+    }
+}
+
+uintptr_t get_function_off(int pid, uintptr_t addr, char *lib) {
+    uintptr_t off = 0;
+    parse_maps(pid, [=, &off](map_info &info) -> bool {
+        if (addr >= info.start && addr < info.end) {
+            if (lib)
+                strcpy(lib, info.path);
+            off = addr - info.start + info.off;
+            return false;
+        }
+        return true;
+    });
+    return off;
+}
+
+uintptr_t get_function_addr(int pid, const char *lib, uintptr_t off) {
+    uintptr_t addr = 0;
+    parse_maps(pid, [=, &addr](map_info &info) -> bool {
+        if (strcmp(info.path, lib) == 0 && (info.perms & map_info::EXEC)) {
+            addr = info.start - info.off + off;
+            return false;
+        }
+        return true;
+    });
+    return addr;
+}