4 files changed, 186 insertions, 137 deletions

diff --git a/minzip/SysUtil.c b/minzip/SysUtil.c
index e6f650644..2cfa39ae3 100644
--- a/minzip/SysUtil.c
+++ b/minzip/SysUtil.c
@@ -8,11 +8,14 @@
 #include <unistd.h>
 #include <string.h>
 #include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <limits.h>
 #include <errno.h>
 #include <assert.h>
 
-#define LOG_TAG "minzip"
+#define LOG_TAG "sysutil"
 #include "Log.h"
 #include "SysUtil.h"
 
@@ -46,13 +49,13 @@ static int getFileStartAndLength(int fd, off_t *start_, size_t *length_)
 }
 
 /*
- * Map a file (from fd's current offset) into a shared, read-only memory
+ * Map a file (from fd's current offset) into a private, read-only memory
  * segment.  The file offset must be a multiple of the page size.
  *
  * On success, returns 0 and fills out "pMap".  On failure, returns a nonzero
  * value and does not disturb "pMap".
  */
-int sysMapFileInShmem(int fd, MemMapping* pMap)
+static int sysMapFD(int fd, MemMapping* pMap)
 {
     off_t start;
     size_t length;
@@ -63,33 +66,146 @@ int sysMapFileInShmem(int fd, MemMapping* pMap)
     if (getFileStartAndLength(fd, &start, &length) < 0)
         return -1;
 
-    memPtr = mmap(NULL, length, PROT_READ, MAP_FILE | MAP_SHARED, fd, start);
+    memPtr = mmap(NULL, length, PROT_READ, MAP_PRIVATE, fd, start);
     if (memPtr == MAP_FAILED) {
-        LOGW("mmap(%d, R, FILE|SHARED, %d, %d) failed: %s\n", (int) length,
+        LOGW("mmap(%d, R, PRIVATE, %d, %d) failed: %s\n", (int) length,
             fd, (int) start, strerror(errno));
         return -1;
     }
 
-    pMap->baseAddr = pMap->addr = memPtr;
-    pMap->baseLength = pMap->length = length;
+    pMap->addr = memPtr;
+    pMap->length = length;
+    pMap->range_count = 1;
+    pMap->ranges = malloc(sizeof(MappedRange));
+    pMap->ranges[0].addr = memPtr;
+    pMap->ranges[0].length = length;
 
     return 0;
 }
 
+static int sysMapBlockFile(FILE* mapf, MemMapping* pMap)
+{
+    char block_dev[PATH_MAX+1];
+    size_t size;
+    unsigned int blksize;
+    unsigned int blocks;
+    unsigned int range_count;
+    unsigned int i;
+
+    if (fgets(block_dev, sizeof(block_dev), mapf) == NULL) {
+        LOGW("failed to read block device from header\n");
+        return -1;
+    }
+    for (i = 0; i < sizeof(block_dev); ++i) {
+        if (block_dev[i] == '\n') {
+            block_dev[i] = 0;
+            break;
+        }
+    }
+
+    if (fscanf(mapf, "%d %d\n%d\n", &size, &blksize, &range_count) != 3) {
+        LOGW("failed to parse block map header\n");
+        return -1;
+    }
+
+    blocks = ((size-1) / blksize) + 1;
+
+    pMap->range_count = range_count;
+    pMap->ranges = malloc(range_count * sizeof(MappedRange));
+    memset(pMap->ranges, 0, range_count * sizeof(MappedRange));
+
+    // Reserve enough contiguous address space for the whole file.
+    unsigned char* reserve;
+    reserve = mmap64(NULL, blocks * blksize, PROT_NONE, MAP_PRIVATE | MAP_ANON, -1, 0);
+    if (reserve == MAP_FAILED) {
+        LOGW("failed to reserve address space: %s\n", strerror(errno));
+        return -1;
+    }
+
+    pMap->ranges[range_count-1].addr = reserve;
+    pMap->ranges[range_count-1].length = blocks * blksize;
+
+    int fd = open(block_dev, O_RDONLY);
+    if (fd < 0) {
+        LOGW("failed to open block device %s: %s\n", block_dev, strerror(errno));
+        return -1;
+    }
+
+    unsigned char* next = reserve;
+    for (i = 0; i < range_count; ++i) {
+        int start, end;
+        if (fscanf(mapf, "%d %d\n", &start, &end) != 2) {
+            LOGW("failed to parse range %d in block map\n", i);
+            return -1;
+        }
+
+        void* addr = mmap64(next, (end-start)*blksize, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, ((off64_t)start)*blksize);
+        if (addr == MAP_FAILED) {
+            LOGW("failed to map block %d: %s\n", i, strerror(errno));
+            return -1;
+        }
+        pMap->ranges[i].addr = addr;
+        pMap->ranges[i].length = (end-start)*blksize;
+
+        next += pMap->ranges[i].length;
+    }
+
+    pMap->addr = reserve;
+    pMap->length = size;
+
+    return 0;
+}
+
+int sysMapFile(const char* fn, MemMapping* pMap)
+{
+    memset(pMap, 0, sizeof(*pMap));
+
+    if (fn && fn[0] == '@') {
+        // A map of blocks
+        FILE* mapf = fopen(fn+1, "r");
+        if (mapf == NULL) {
+            LOGV("Unable to open '%s': %s\n", fn+1, strerror(errno));
+            return -1;
+        }
+
+        if (sysMapBlockFile(mapf, pMap) != 0) {
+            LOGW("Map of '%s' failed\n", fn);
+            return -1;
+        }
+
+        fclose(mapf);
+    } else {
+        // This is a regular file.
+        int fd = open(fn, O_RDONLY, 0);
+        if (fd < 0) {
+            LOGE("Unable to open '%s': %s\n", fn, strerror(errno));
+            return -1;
+        }
+
+        if (sysMapFD(fd, pMap) != 0) {
+            LOGE("Map of '%s' failed\n", fn);
+            close(fd);
+            return -1;
+        }
+
+        close(fd);
+    }
+    return 0;
+}
+
 /*
  * Release a memory mapping.
  */
-void sysReleaseShmem(MemMapping* pMap)
+void sysReleaseMap(MemMapping* pMap)
 {
-    if (pMap->baseAddr == NULL && pMap->baseLength == 0)
-        return;
-
-    if (munmap(pMap->baseAddr, pMap->baseLength) < 0) {
-        LOGW("munmap(%p, %d) failed: %s\n",
-            pMap->baseAddr, (int)pMap->baseLength, strerror(errno));
-    } else {
-        LOGV("munmap(%p, %d) succeeded\n", pMap->baseAddr, pMap->baseLength);
-        pMap->baseAddr = NULL;
-        pMap->baseLength = 0;
+    int i;
+    for (i = 0; i < pMap->range_count; ++i) {
+        if (munmap(pMap->ranges[i].addr, pMap->ranges[i].length) < 0) {
+            LOGW("munmap(%p, %d) failed: %s\n",
+                 pMap->ranges[i].addr, (int)pMap->ranges[i].length, strerror(errno));
+        }
     }
+    free(pMap->ranges);
+    pMap->ranges = NULL;
+    pMap->range_count = 0;
 }
diff --git a/minzip/SysUtil.h b/minzip/SysUtil.h
index 55cd0e769..7adff1e54 100644
--- a/minzip/SysUtil.h
+++ b/minzip/SysUtil.h
@@ -6,39 +6,47 @@
 #ifndef _MINZIP_SYSUTIL
 #define _MINZIP_SYSUTIL
 
-#include "inline_magic.h"
-
+#include <stdio.h>
 #include <sys/types.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct MappedRange {
+    void* addr;
+    size_t length;
+} MappedRange;
+
 /*
  * Use this to keep track of mapped segments.
  */
 typedef struct MemMapping {
-    void*   addr;           /* start of data */
-    size_t  length;         /* length of data */
+    unsigned char* addr;           /* start of data */
+    size_t         length;         /* length of data */
 
-    void*   baseAddr;       /* page-aligned base address */
-    size_t  baseLength;     /* length of mapping */
+    int            range_count;
+    MappedRange*   ranges;
 } MemMapping;
 
-/* copy a map */
-INLINE void sysCopyMap(MemMapping* dst, const MemMapping* src) {
-    *dst = *src;
-}
-
 /*
- * Map a file (from fd's current offset) into a shared,
- * read-only memory segment.
+ * Map a file into a private, read-only memory segment.  If 'fn'
+ * begins with an '@' character, it is a map of blocks to be mapped,
+ * otherwise it is treated as an ordinary file.
  *
  * On success, "pMap" is filled in, and zero is returned.
  */
-int sysMapFileInShmem(int fd, MemMapping* pMap);
+int sysMapFile(const char* fn, MemMapping* pMap);
 
 /*
  * Release the pages associated with a shared memory segment.
  *
  * This does not free "pMap"; it just releases the memory.
  */
-void sysReleaseShmem(MemMapping* pMap);
+void sysReleaseMap(MemMapping* pMap);
+
+#ifdef __cplusplus
+}
+#endif
 
 #endif /*_MINZIP_SYSUTIL*/
diff --git a/minzip/Zip.c b/minzip/Zip.c
index 439e5d9cd..6752bced5 100644
--- a/minzip/Zip.c
+++ b/minzip/Zip.c
@@ -184,7 +184,7 @@ static int validFilename(const char *fileName, unsigned int fileNameLen)
  *
  * Returns "true" on success.
  */
-static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
+static bool parseZipArchive(ZipArchive* pArchive)
 {
     bool result = false;
     const unsigned char* ptr;
@@ -196,7 +196,7 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
      * signature for the first file (LOCSIG) or, if the archive doesn't
      * have any files in it, the end-of-central-directory signature (ENDSIG).
      */
-    val = get4LE(pMap->addr);
+    val = get4LE(pArchive->addr);
     if (val == ENDSIG) {
         LOGI("Found Zip archive, but it looks empty\n");
         goto bail;
@@ -209,14 +209,14 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
      * Find the EOCD.  We'll find it immediately unless they have a file
      * comment.
      */
-    ptr = pMap->addr + pMap->length - ENDHDR;
+    ptr = pArchive->addr + pArchive->length - ENDHDR;
 
-    while (ptr >= (const unsigned char*) pMap->addr) {
+    while (ptr >= (const unsigned char*) pArchive->addr) {
         if (*ptr == (ENDSIG & 0xff) && get4LE(ptr) == ENDSIG)
             break;
         ptr--;
     }
-    if (ptr < (const unsigned char*) pMap->addr) {
+    if (ptr < (const unsigned char*) pArchive->addr) {
         LOGI("Could not find end-of-central-directory in Zip\n");
         goto bail;
     }
@@ -230,9 +230,9 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
     cdOffset = get4LE(ptr + ENDOFF);
 
     LOGVV("numEntries=%d cdOffset=%d\n", numEntries, cdOffset);
-    if (numEntries == 0 || cdOffset >= pMap->length) {
+    if (numEntries == 0 || cdOffset >= pArchive->length) {
         LOGW("Invalid entries=%d offset=%d (len=%zd)\n",
-            numEntries, cdOffset, pMap->length);
+            numEntries, cdOffset, pArchive->length);
         goto bail;
     }
 
@@ -245,14 +245,14 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
     if (pArchive->pEntries == NULL || pArchive->pHash == NULL)
         goto bail;
 
-    ptr = pMap->addr + cdOffset;
+    ptr = pArchive->addr + cdOffset;
     for (i = 0; i < numEntries; i++) {
         ZipEntry* pEntry;
         unsigned int fileNameLen, extraLen, commentLen, localHdrOffset;
         const unsigned char* localHdr;
         const char *fileName;
 
-        if (ptr + CENHDR > (const unsigned char*)pMap->addr + pMap->length) {
+        if (ptr + CENHDR > (const unsigned char*)pArchive->addr + pArchive->length) {
             LOGW("Ran off the end (at %d)\n", i);
             goto bail;
         }
@@ -266,7 +266,7 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
         extraLen = get2LE(ptr + CENEXT);
         commentLen = get2LE(ptr + CENCOM);
         fileName = (const char*)ptr + CENHDR;
-        if (fileName + fileNameLen > (const char*)pMap->addr + pMap->length) {
+        if (fileName + fileNameLen > (const char*)pArchive->addr + pArchive->length) {
             LOGW("Filename ran off the end (at %d)\n", i);
             goto bail;
         }
@@ -352,15 +352,15 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
         }
         pEntry->externalFileAttributes = get4LE(ptr + CENATX);
 
-        // Perform pMap->addr + localHdrOffset, ensuring that it won't
+        // Perform pArchive->addr + localHdrOffset, ensuring that it won't
         // overflow. This is needed because localHdrOffset is untrusted.
-        if (!safe_add((uintptr_t *)&localHdr, (uintptr_t)pMap->addr,
+        if (!safe_add((uintptr_t *)&localHdr, (uintptr_t)pArchive->addr,
             (uintptr_t)localHdrOffset)) {
             LOGW("Integer overflow adding in parseZipArchive\n");
             goto bail;
         }
         if ((uintptr_t)localHdr + LOCHDR >
-            (uintptr_t)pMap->addr + pMap->length) {
+            (uintptr_t)pArchive->addr + pArchive->length) {
             LOGW("Bad offset to local header: %d (at %d)\n", localHdrOffset, i);
             goto bail;
         }
@@ -374,7 +374,7 @@ static bool parseZipArchive(ZipArchive* pArchive, const MemMapping* pMap)
             LOGW("Integer overflow adding in parseZipArchive\n");
             goto bail;
         }
-        if ((size_t)pEntry->offset + pEntry->compLen > pMap->length) {
+        if ((size_t)pEntry->offset + pEntry->compLen > pArchive->length) {
             LOGW("Data ran off the end (at %d)\n", i);
             goto bail;
         }
@@ -427,50 +427,30 @@ bail:
  *
  * On success, we fill out the contents of "pArchive".
  */
-int mzOpenZipArchive(const char* fileName, ZipArchive* pArchive)
+int mzOpenZipArchive(unsigned char* addr, size_t length, ZipArchive* pArchive)
 {
-    MemMapping map;
     int err;
 
-    LOGV("Opening archive '%s' %p\n", fileName, pArchive);
-
-    map.addr = NULL;
-    memset(pArchive, 0, sizeof(*pArchive));
-
-    pArchive->fd = open(fileName, O_RDONLY, 0);
-    if (pArchive->fd < 0) {
-        err = errno ? errno : -1;
-        LOGV("Unable to open '%s': %s\n", fileName, strerror(err));
-        goto bail;
-    }
-
-    if (sysMapFileInShmem(pArchive->fd, &map) != 0) {
-        err = -1;
-        LOGW("Map of '%s' failed\n", fileName);
-        goto bail;
-    }
-
-    if (map.length < ENDHDR) {
+    if (length < ENDHDR) {
         err = -1;
         LOGV("File '%s' too small to be zip (%zd)\n", fileName, map.length);
         goto bail;
     }
 
-    if (!parseZipArchive(pArchive, &map)) {
+    pArchive->addr = addr;
+    pArchive->length = length;
+
+    if (!parseZipArchive(pArchive)) {
         err = -1;
         LOGV("Parsing '%s' failed\n", fileName);
         goto bail;
     }
 
     err = 0;
-    sysCopyMap(&pArchive->map, &map);
-    map.addr = NULL;
 
 bail:
     if (err != 0)
         mzCloseZipArchive(pArchive);
-    if (map.addr != NULL)
-        sysReleaseShmem(&map);
     return err;
 }
 
@@ -483,16 +463,10 @@ void mzCloseZipArchive(ZipArchive* pArchive)
 {
     LOGV("Closing archive %p\n", pArchive);
 
-    if (pArchive->fd >= 0)
-        close(pArchive->fd);
-    if (pArchive->map.addr != NULL)
-        sysReleaseShmem(&pArchive->map);
-
     free(pArchive->pEntries);
 
     mzHashTableFree(pArchive->pHash);
 
-    pArchive->fd = -1;
     pArchive->pHash = NULL;
     pArchive->pEntries = NULL;
 }
@@ -528,29 +502,7 @@ static bool processStoredEntry(const ZipArchive *pArchive,
     const ZipEntry *pEntry, ProcessZipEntryContentsFunction processFunction,
     void *cookie)
 {
-    size_t bytesLeft = pEntry->compLen;
-    while (bytesLeft > 0) {
-        unsigned char buf[32 * 1024];
-        ssize_t n;
-        size_t count;
-        bool ret;
-
-        count = bytesLeft;
-        if (count > sizeof(buf)) {
-            count = sizeof(buf);
-        }
-        n = read(pArchive->fd, buf, count);
-        if (n < 0 || (size_t)n != count) {
-            LOGE("Can't read %zu bytes from zip file: %ld\n", count, n);
-            return false;
-        }
-        ret = processFunction(buf, n, cookie);
-        if (!ret) {
-            return false;
-        }
-        bytesLeft -= count;
-    }
-    return true;
+    return processFunction(pArchive->addr + pEntry->offset, pEntry->uncompLen, cookie);
 }
 
 static bool processDeflatedEntry(const ZipArchive *pArchive,
@@ -573,8 +525,8 @@ static bool processDeflatedEntry(const ZipArchive *pArchive,
     zstream.zalloc = Z_NULL;
     zstream.zfree = Z_NULL;
     zstream.opaque = Z_NULL;
-    zstream.next_in = NULL;
-    zstream.avail_in = 0;
+    zstream.next_in = pArchive->addr + pEntry->offset;
+    zstream.avail_in = pEntry->compLen;
     zstream.next_out = (Bytef*) procBuf;
     zstream.avail_out = sizeof(procBuf);
     zstream.data_type = Z_UNKNOWN;
@@ -598,25 +550,6 @@ static bool processDeflatedEntry(const ZipArchive *pArchive,
      * Loop while we have data.
      */
     do {
-        /* read as much as we can */
-        if (zstream.avail_in == 0) {
-            long getSize = (compRemaining > (long)sizeof(readBuf)) ?
-                        (long)sizeof(readBuf) : compRemaining;
-            LOGVV("+++ reading %ld bytes (%ld left)\n",
-                getSize, compRemaining);
-
-            int cc = read(pArchive->fd, readBuf, getSize);
-            if (cc != (int) getSize) {
-                LOGW("inflate read failed (%d vs %ld)\n", cc, getSize);
-                goto z_bail;
-            }
-
-            compRemaining -= getSize;
-
-            zstream.next_in = readBuf;
-            zstream.avail_in = getSize;
-        }
-
         /* uncompress the data */
         zerr = inflate(&zstream, Z_NO_FLUSH);
         if (zerr != Z_OK && zerr != Z_STREAM_END) {
@@ -676,12 +609,6 @@ bool mzProcessZipEntryContents(const ZipArchive *pArchive,
     bool ret = false;
     off_t oldOff;
 
-    /* save current offset */
-    oldOff = lseek(pArchive->fd, 0, SEEK_CUR);
-
-    /* Seek to the beginning of the entry's compressed data. */
-    lseek(pArchive->fd, pEntry->offset, SEEK_SET);
-
     switch (pEntry->compression) {
     case STORED:
         ret = processStoredEntry(pArchive, pEntry, processFunction, cookie);
@@ -695,8 +622,6 @@ bool mzProcessZipEntryContents(const ZipArchive *pArchive,
         break;
     }
 
-    /* restore file offset */
-    lseek(pArchive->fd, oldOff, SEEK_SET);
     return ret;
 }
 
diff --git a/minzip/Zip.h b/minzip/Zip.h
index c94282827..05a2e60e0 100644
--- a/minzip/Zip.h
+++ b/minzip/Zip.h
@@ -46,11 +46,11 @@ typedef struct ZipEntry {
  * One Zip archive.  Treat as opaque.
  */
 typedef struct ZipArchive {
-    int         fd;
-    unsigned int numEntries;
-    ZipEntry*   pEntries;
-    HashTable*  pHash;          // maps file name to ZipEntry
-    MemMapping  map;
+    unsigned int   numEntries;
+    ZipEntry*      pEntries;
+    HashTable*     pHash;          // maps file name to ZipEntry
+    unsigned char* addr;
+    size_t         length;
 } ZipArchive;
 
 /*
@@ -68,7 +68,7 @@ typedef struct {
  * On success, returns 0 and populates "pArchive".  Returns nonzero errno
  * value on failure.
  */
-int mzOpenZipArchive(const char* fileName, ZipArchive* pArchive);
+int mzOpenZipArchive(unsigned char* addr, size_t length, ZipArchive* pArchive);
 
 /*
  * Close archive, releasing resources associated with it.