diff --git a/cmds/idmap/inspect.cpp b/cmds/idmap/inspect.cpp
new file mode 100644
index 0000000..a59f5d3
--- /dev/null
+++ b/cmds/idmap/inspect.cpp
@@ -0,0 +1,291 @@
+#include "idmap.h"
+
+#include <androidfw/AssetManager.h>
+#include <androidfw/ResourceTypes.h>
+#include <utils/String8.h>
+
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+using namespace android;
+
+#define NEXT(b, i, o) do { if (buf.next(&i, &o) < 0) { return -1; } } while (0)
+
+namespace {
+    static const uint32_t IDMAP_MAGIC = 0x706d6469;
+    static const size_t PATH_LENGTH = 256;
+    static const uint32_t IDMAP_HEADER_SIZE = (3 + 2 * (PATH_LENGTH / sizeof(uint32_t)));
+
+    void printe(const char *fmt, ...);
+
+    class IdmapBuffer {
+        private:
+            char *buf_;
+            size_t len_;
+            mutable size_t pos_;
+        public:
+            IdmapBuffer() : buf_((char *)MAP_FAILED), len_(0), pos_(0) {}
+
+            ~IdmapBuffer() {
+                if (buf_ != MAP_FAILED) {
+                    munmap(buf_, len_);
+                }
+            }
+
+            int init(const char *idmap_path)
+            {
+                struct stat st;
+                int fd;
+
+                if (stat(idmap_path, &st) < 0) {
+                    printe("failed to stat idmap '%s': %s\n", idmap_path, strerror(errno));
+                    return -1;
+                }
+                len_ = st.st_size;
+                if ((fd = TEMP_FAILURE_RETRY(open(idmap_path, O_RDONLY))) < 0) {
+                    printe("failed to open idmap '%s': %s\n", idmap_path, strerror(errno));
+                    return -1;
+                }
+                if ((buf_ = (char*)mmap(NULL, len_, PROT_READ, MAP_PRIVATE, fd, 0)) == MAP_FAILED) {
+                    close(fd);
+                    printe("failed to mmap idmap: %s\n", strerror(errno));
+                    return -1;
+                }
+                close(fd);
+                return 0;
+            }
+
+            int next(uint32_t *i, uint32_t *offset) const
+            {
+                if (!buf_) {
+                    printe("failed to read next uint32_t: buffer not initialized\n");
+                    return -1;
+                }
+                if (pos_ + 4 > len_) {
+                    printe("failed to read next uint32_t: end of buffer reached at pos=0x%08x\n",
+                            pos_);
+                    return -1;
+                }
+                *offset = pos_ / sizeof(uint32_t);
+                char a = buf_[pos_++];
+                char b = buf_[pos_++];
+                char c = buf_[pos_++];
+                char d = buf_[pos_++];
+                *i = (d << 24) | (c << 16) | (b << 8) | a;
+                return 0;
+            }
+
+            int nextPath(char *b, uint32_t *offset_start, uint32_t *offset_end) const
+            {
+                if (!buf_) {
+                    printe("failed to read next path: buffer not initialized\n");
+                    return -1;
+                }
+                if (pos_ + PATH_LENGTH > len_) {
+                    printe("failed to read next path: end of buffer reached at pos=0x%08x\n", pos_);
+                    return -1;
+                }
+                memcpy(b, buf_ + pos_, PATH_LENGTH);
+                *offset_start = pos_ / sizeof(uint32_t);
+                pos_ += PATH_LENGTH;
+                *offset_end = pos_ / sizeof(uint32_t) - 1;
+                return 0;
+            }
+    };
+
+    void printe(const char *fmt, ...)
+    {
+        va_list ap;
+
+        va_start(ap, fmt);
+        fprintf(stderr, "error: ");
+        vfprintf(stderr, fmt, ap);
+        va_end(ap);
+    }
+
+    void print_header()
+    {
+        printf("SECTION      ENTRY        VALUE      OFFSET    COMMENT\n");
+    }
+
+    void print(const char *section, const char *subsection, uint32_t value, uint32_t offset,
+            const char *fmt, ...)
+    {
+        va_list ap;
+
+        va_start(ap, fmt);
+        printf("%-12s %-12s 0x%08x 0x%-4x    ", section, subsection, value, offset);
+        vprintf(fmt, ap);
+        printf("\n");
+        va_end(ap);
+    }
+
+    void print_path(const char *section, const char *subsection, uint32_t offset_start,
+            uint32_t offset_end, const char *fmt, ...)
+    {
+        va_list ap;
+
+        va_start(ap, fmt);
+        printf("%-12s %-12s .......... 0x%02x-0x%02x ", section, subsection, offset_start,
+                offset_end);
+        vprintf(fmt, ap);
+        printf("\n");
+        va_end(ap);
+    }
+
+    int resource_metadata(const AssetManager& am, uint32_t res_id,
+            String8 *package, String8 *type, String8 *name)
+    {
+        const ResTable& rt = am.getResources();
+        struct ResTable::resource_name data;
+        if (!rt.getResourceName(res_id, false, &data)) {
+            printe("failed to get resource name id=0x%08x\n", res_id);
+            return -1;
+        }
+        if (package) {
+            *package = String8(String16(data.package, data.packageLen));
+        }
+        if (type) {
+            *type = String8(String16(data.type, data.typeLen));
+        }
+        if (name) {
+            *name = String8(String16(data.name, data.nameLen));
+        }
+        return 0;
+    }
+
+    int package_id(const AssetManager& am)
+    {
+        return (am.getResources().getBasePackageId(0)) << 24;
+    }
+
+    int parse_idmap_header(const IdmapBuffer& buf, AssetManager& am)
+    {
+        uint32_t i, o, e;
+        char path[PATH_LENGTH];
+
+        NEXT(buf, i, o);
+        if (i != IDMAP_MAGIC) {
+            printe("not an idmap file: actual magic constant 0x%08x does not match expected magic "
+                    "constant 0x%08x\n", i, IDMAP_MAGIC);
+            return -1;
+        }
+        print_header();
+        print("IDMAP HEADER", "magic", i, o, "");
+
+        NEXT(buf, i, o);
+        print("", "base crc", i, o, "");
+
+        NEXT(buf, i, o);
+        print("", "overlay crc", i, o, "");
+
+        if (buf.nextPath(path, &o, &e) < 0) {
+            // printe done from IdmapBuffer::nextPath
+            return -1;
+        }
+        print_path("", "base path", o, e, "%s", path);
+        if (!am.addAssetPath(String8(path), NULL)) {
+            printe("failed to add '%s' as asset path\n", path);
+            return -1;
+        }
+
+        if (buf.nextPath(path, &o, &e) < 0) {
+            // printe done from IdmapBuffer::nextPath
+            return -1;
+        }
+        print_path("", "overlay path", o, e, "%s", path);
+
+        return 0;
+    }
+
+    int parse_data_header(const IdmapBuffer& buf, const AssetManager& am, Vector<uint32_t>& types)
+    {
+        uint32_t i, o;
+        const uint32_t numeric_package = package_id(am);
+
+        NEXT(buf, i, o);
+        print("DATA HEADER", "types count", i, o, "");
+        const uint32_t N = i;
+
+        for (uint32_t j = 0; j < N; ++j) {
+            NEXT(buf, i, o);
+            if (i == 0) {
+                print("", "padding", i, o, "");
+            } else {
+                String8 type;
+                const uint32_t numeric_type = (j + 1) << 16;
+                const uint32_t res_id = numeric_package | numeric_type;
+                if (resource_metadata(am, res_id, NULL, &type, NULL) < 0) {
+                    // printe done from resource_metadata
+                    return -1;
+                }
+                print("", "type offset", i, o, "absolute offset 0x%02x, %s",
+                        i + IDMAP_HEADER_SIZE, type.string());
+                types.add(numeric_type);
+            }
+        }
+
+        return 0;
+    }
+
+    int parse_data_block(const IdmapBuffer& buf, const AssetManager& am, size_t numeric_type)
+    {
+        uint32_t i, o, n, id_offset;
+        const uint32_t numeric_package = package_id(am);
+
+        NEXT(buf, i, o);
+        print("DATA BLOCK", "entry count", i, o, "");
+        n = i;
+
+        NEXT(buf, i, o);
+        print("", "entry offset", i, o, "");
+        id_offset = i;
+
+        for ( ; n > 0; --n) {
+            String8 type, name;
+
+            NEXT(buf, i, o);
+            if (i == 0) {
+                print("", "padding", i, o, "");
+            } else {
+                uint32_t res_id = numeric_package | numeric_type | id_offset;
+                if (resource_metadata(am, res_id, NULL, &type, &name) < 0) {
+                    // printe done from resource_metadata
+                    return -1;
+                }
+                print("", "entry", i, o, "%s/%s", type.string(), name.string());
+            }
+            ++id_offset;
+        }
+
+        return 0;
+    }
+}
+
+int idmap_inspect(const char *idmap_path)
+{
+    IdmapBuffer buf;
+    if (buf.init(idmap_path) < 0) {
+        // printe done from IdmapBuffer::init
+        return EXIT_FAILURE;
+    }
+    AssetManager am;
+    if (parse_idmap_header(buf, am) < 0) {
+        // printe done from parse_idmap_header
+        return EXIT_FAILURE;
+    }
+    Vector<uint32_t> types;
+    if (parse_data_header(buf, am, types) < 0) {
+        // printe done from parse_data_header
+        return EXIT_FAILURE;
+    }
+    const size_t N = types.size();
+    for (size_t i = 0; i < N; ++i) {
+        if (parse_data_block(buf, am, types.itemAt(i)) < 0) {
+            // printe done from parse_data_block
+            return EXIT_FAILURE;
+        }
+    }
+    return EXIT_SUCCESS;
+}