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-rw-r--r--minzip/SysUtil.c239
1 files changed, 120 insertions, 119 deletions
diff --git a/minzip/SysUtil.c b/minzip/SysUtil.c
index 31c76d6d4..ac6f5c33f 100644
--- a/minzip/SysUtil.c
+++ b/minzip/SysUtil.c
@@ -8,42 +8,17 @@
#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"
-/*
- * Having trouble finding a portable way to get this. sysconf(_SC_PAGE_SIZE)
- * seems appropriate, but we don't have that on the device. Some systems
- * have getpagesize(2), though the linux man page has some odd cautions.
- */
-#define DEFAULT_PAGE_SIZE 4096
-
-
-/*
- * Create an anonymous shared memory segment large enough to hold "length"
- * bytes. The actual segment may be larger because mmap() operates on
- * page boundaries (usually 4K).
- */
-static void* sysCreateAnonShmem(size_t length)
-{
- void* ptr;
-
- ptr = mmap(NULL, length, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_ANON, -1, 0);
- if (ptr == MAP_FAILED) {
- LOGW("mmap(%d, RW, SHARED|ANON) failed: %s\n", (int) length,
- strerror(errno));
- return NULL;
- }
-
- return ptr;
-}
-
static int getFileStartAndLength(int fd, off_t *start_, size_t *length_)
{
off_t start, end;
@@ -74,48 +49,13 @@ static int getFileStartAndLength(int fd, off_t *start_, size_t *length_)
}
/*
- * Pull the contents of a file into an new shared memory segment. We grab
- * everything from fd's current offset on.
- *
- * We need to know the length ahead of time so we can allocate a segment
- * of sufficient size.
- */
-int sysLoadFileInShmem(int fd, MemMapping* pMap)
-{
- off_t start;
- size_t length, actual;
- void* memPtr;
-
- assert(pMap != NULL);
-
- if (getFileStartAndLength(fd, &start, &length) < 0)
- return -1;
-
- memPtr = sysCreateAnonShmem(length);
- if (memPtr == NULL)
- return -1;
-
- pMap->baseAddr = pMap->addr = memPtr;
- pMap->baseLength = pMap->length = length;
-
- actual = TEMP_FAILURE_RETRY(read(fd, memPtr, length));
- if (actual != length) {
- LOGE("only read %d of %d bytes\n", (int) actual, (int) length);
- sysReleaseShmem(pMap);
- return -1;
- }
-
- return 0;
-}
-
-/*
- * 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;
@@ -126,87 +66,148 @@ 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;
}
-/*
- * Map part of a file (from fd's current offset) into a shared, read-only
- * memory segment.
- *
- * On success, returns 0 and fills out "pMap". On failure, returns a nonzero
- * value and does not disturb "pMap".
- */
-int sysMapFileSegmentInShmem(int fd, off_t start, long length,
- MemMapping* pMap)
+static int sysMapBlockFile(FILE* mapf, MemMapping* pMap)
{
- off_t dummy;
- size_t fileLength, actualLength;
- off_t actualStart;
- int adjust;
- void* memPtr;
-
- assert(pMap != NULL);
+ 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 (getFileStartAndLength(fd, &dummy, &fileLength) < 0)
+ if (fscanf(mapf, "%zu %u\n%u\n", &size, &blksize, &range_count) != 3) {
+ LOGW("failed to parse block map header\n");
return -1;
+ }
- if (start + length > (long)fileLength) {
- LOGW("bad segment: st=%d len=%ld flen=%d\n",
- (int) start, length, (int) fileLength);
+ 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;
}
- /* adjust to be page-aligned */
- adjust = start % DEFAULT_PAGE_SIZE;
- actualStart = start - adjust;
- actualLength = length + adjust;
+ pMap->ranges[range_count-1].addr = reserve;
+ pMap->ranges[range_count-1].length = blocks * blksize;
- memPtr = mmap(NULL, actualLength, PROT_READ, MAP_FILE | MAP_SHARED,
- fd, actualStart);
- if (memPtr == MAP_FAILED) {
- LOGW("mmap(%d, R, FILE|SHARED, %d, %d) failed: %s\n",
- (int) actualLength, fd, (int) actualStart, strerror(errno));
+ 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;
}
- pMap->baseAddr = memPtr;
- pMap->baseLength = actualLength;
- pMap->addr = (char*)memPtr + adjust;
- pMap->length = length;
+ 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;
- LOGVV("mmap seg (st=%d ln=%d): bp=%p bl=%d ad=%p ln=%d\n",
- (int) start, (int) length,
- pMap->baseAddr, (int) pMap->baseLength,
- pMap->addr, (int) pMap->length);
+ LOGI("mmapped %d ranges\n", range_count);
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;
}
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 19:29:32 +0100