diff options
Diffstat (limited to 'minzipold/SysUtil.c')
-rw-r--r-- | minzipold/SysUtil.c | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/minzipold/SysUtil.c b/minzipold/SysUtil.c deleted file mode 100644 index 31c76d6d4..000000000 --- a/minzipold/SysUtil.c +++ /dev/null @@ -1,212 +0,0 @@ -/* - * Copyright 2006 The Android Open Source Project - * - * System utilities. - */ -#include <stdlib.h> -#include <stdio.h> -#include <unistd.h> -#include <string.h> -#include <sys/mman.h> -#include <limits.h> -#include <errno.h> -#include <assert.h> - -#define LOG_TAG "minzip" -#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; - size_t length; - - assert(start_ != NULL); - assert(length_ != NULL); - - start = lseek(fd, 0L, SEEK_CUR); - end = lseek(fd, 0L, SEEK_END); - (void) lseek(fd, start, SEEK_SET); - - if (start == (off_t) -1 || end == (off_t) -1) { - LOGE("could not determine length of file\n"); - return -1; - } - - length = end - start; - if (length == 0) { - LOGE("file is empty\n"); - return -1; - } - - *start_ = start; - *length_ = length; - - return 0; -} - -/* - * 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 - * 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) -{ - off_t start; - size_t length; - void* memPtr; - - assert(pMap != NULL); - - if (getFileStartAndLength(fd, &start, &length) < 0) - return -1; - - memPtr = mmap(NULL, length, PROT_READ, MAP_FILE | MAP_SHARED, fd, start); - if (memPtr == MAP_FAILED) { - LOGW("mmap(%d, R, FILE|SHARED, %d, %d) failed: %s\n", (int) length, - fd, (int) start, strerror(errno)); - return -1; - } - - pMap->baseAddr = pMap->addr = memPtr; - pMap->baseLength = pMap->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) -{ - off_t dummy; - size_t fileLength, actualLength; - off_t actualStart; - int adjust; - void* memPtr; - - assert(pMap != NULL); - - if (getFileStartAndLength(fd, &dummy, &fileLength) < 0) - return -1; - - if (start + length > (long)fileLength) { - LOGW("bad segment: st=%d len=%ld flen=%d\n", - (int) start, length, (int) fileLength); - return -1; - } - - /* adjust to be page-aligned */ - adjust = start % DEFAULT_PAGE_SIZE; - actualStart = start - adjust; - actualLength = length + adjust; - - 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)); - return -1; - } - - pMap->baseAddr = memPtr; - pMap->baseLength = actualLength; - pMap->addr = (char*)memPtr + adjust; - pMap->length = length; - - 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); - - return 0; -} - -/* - * Release a memory mapping. - */ -void sysReleaseShmem(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; - } -} - |