diff options
Diffstat (limited to 'otautil/SysUtil.cpp')
-rw-r--r-- | otautil/SysUtil.cpp | 126 |
1 files changed, 58 insertions, 68 deletions
diff --git a/otautil/SysUtil.cpp b/otautil/SysUtil.cpp index a2133b953..dfa215073 100644 --- a/otautil/SysUtil.cpp +++ b/otautil/SysUtil.cpp @@ -16,14 +16,12 @@ #include "SysUtil.h" -#include <errno.h> #include <fcntl.h> -#include <stdint.h> +#include <stdint.h> // SIZE_MAX #include <sys/mman.h> #include <sys/stat.h> #include <sys/types.h> -#include <algorithm> #include <string> #include <vector> @@ -32,9 +30,7 @@ #include <android-base/strings.h> #include <android-base/unique_fd.h> -static bool sysMapFD(int fd, MemMapping* pMap) { - CHECK(pMap != nullptr); - +bool MemMapping::MapFD(int fd) { struct stat sb; if (fstat(fd, &sb) == -1) { PLOG(ERROR) << "fstat(" << fd << ") failed"; @@ -47,50 +43,49 @@ static bool sysMapFD(int fd, MemMapping* pMap) { return false; } - pMap->addr = static_cast<unsigned char*>(memPtr); - pMap->length = sb.st_size; - pMap->ranges.push_back({ memPtr, static_cast<size_t>(sb.st_size) }); + addr = static_cast<unsigned char*>(memPtr); + length = sb.st_size; + ranges_.clear(); + ranges_.emplace_back(MappedRange{ memPtr, static_cast<size_t>(sb.st_size) }); return true; } // A "block map" which looks like this (from uncrypt/uncrypt.cpp): // -// /dev/block/platform/msm_sdcc.1/by-name/userdata # block device -// 49652 4096 # file size in bytes, block size -// 3 # count of block ranges -// 1000 1008 # block range 0 -// 2100 2102 # ... block range 1 -// 30 33 # ... block range 2 +// /dev/block/platform/msm_sdcc.1/by-name/userdata # block device +// 49652 4096 # file size in bytes, block size +// 3 # count of block ranges +// 1000 1008 # block range 0 +// 2100 2102 # ... block range 1 +// 30 33 # ... block range 2 // -// Each block range represents a half-open interval; the line "30 33" -// reprents the blocks [30, 31, 32]. -static int sysMapBlockFile(const char* filename, MemMapping* pMap) { - CHECK(pMap != nullptr); - +// Each block range represents a half-open interval; the line "30 33" reprents the blocks +// [30, 31, 32]. +bool MemMapping::MapBlockFile(const std::string& filename) { std::string content; if (!android::base::ReadFileToString(filename, &content)) { PLOG(ERROR) << "Failed to read " << filename; - return -1; + return false; } std::vector<std::string> lines = android::base::Split(android::base::Trim(content), "\n"); if (lines.size() < 4) { LOG(ERROR) << "Block map file is too short: " << lines.size(); - return -1; + return false; } size_t size; - unsigned int blksize; - if (sscanf(lines[1].c_str(), "%zu %u", &size, &blksize) != 2) { + size_t blksize; + if (sscanf(lines[1].c_str(), "%zu %zu", &size, &blksize) != 2) { LOG(ERROR) << "Failed to parse file size and block size: " << lines[1]; - return -1; + return false; } size_t range_count; if (sscanf(lines[2].c_str(), "%zu", &range_count) != 1) { LOG(ERROR) << "Failed to parse block map header: " << lines[2]; - return -1; + return false; } size_t blocks; @@ -101,14 +96,14 @@ static int sysMapBlockFile(const char* filename, MemMapping* pMap) { lines.size() != 3 + range_count) { LOG(ERROR) << "Invalid data in block map file: size " << size << ", blksize " << blksize << ", range_count " << range_count << ", lines " << lines.size(); - return -1; + return false; } // Reserve enough contiguous address space for the whole file. void* reserve = mmap64(nullptr, blocks * blksize, PROT_NONE, MAP_PRIVATE | MAP_ANON, -1, 0); if (reserve == MAP_FAILED) { PLOG(ERROR) << "failed to reserve address space"; - return -1; + return false; } const std::string& block_dev = lines[0]; @@ -116,10 +111,10 @@ static int sysMapBlockFile(const char* filename, MemMapping* pMap) { if (fd == -1) { PLOG(ERROR) << "failed to open block device " << block_dev; munmap(reserve, blocks * blksize); - return -1; + return false; } - pMap->ranges.resize(range_count); + ranges_.clear(); unsigned char* next = static_cast<unsigned char*>(reserve); size_t remaining_size = blocks * blksize; @@ -129,84 +124,79 @@ static int sysMapBlockFile(const char* filename, MemMapping* pMap) { size_t start, end; if (sscanf(line.c_str(), "%zu %zu\n", &start, &end) != 2) { - LOG(ERROR) << "failed to parse range " << i << " in block map: " << line; + LOG(ERROR) << "failed to parse range " << i << ": " << line; success = false; break; } - size_t length = (end - start) * blksize; - if (end <= start || (end - start) > SIZE_MAX / blksize || length > remaining_size) { - LOG(ERROR) << "unexpected range in block map: " << start << " " << end; + size_t range_size = (end - start) * blksize; + if (end <= start || (end - start) > SIZE_MAX / blksize || range_size > remaining_size) { + LOG(ERROR) << "Invalid range: " << start << " " << end; success = false; break; } - void* addr = mmap64(next, length, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, - static_cast<off64_t>(start) * blksize); - if (addr == MAP_FAILED) { - PLOG(ERROR) << "failed to map block " << i; + void* range_start = mmap64(next, range_size, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, + static_cast<off64_t>(start) * blksize); + if (range_start == MAP_FAILED) { + PLOG(ERROR) << "failed to map range " << i << ": " << line; success = false; break; } - pMap->ranges[i].addr = addr; - pMap->ranges[i].length = length; + ranges_.emplace_back(MappedRange{ range_start, range_size }); - next += length; - remaining_size -= length; + next += range_size; + remaining_size -= range_size; } if (success && remaining_size != 0) { - LOG(ERROR) << "ranges in block map are invalid: remaining_size = " << remaining_size; + LOG(ERROR) << "Invalid ranges: remaining_size " << remaining_size; success = false; } if (!success) { munmap(reserve, blocks * blksize); - return -1; + return false; } - pMap->addr = static_cast<unsigned char*>(reserve); - pMap->length = size; + addr = static_cast<unsigned char*>(reserve); + length = size; LOG(INFO) << "mmapped " << range_count << " ranges"; - return 0; + return true; } -int sysMapFile(const char* fn, MemMapping* pMap) { - if (fn == nullptr || pMap == nullptr) { - LOG(ERROR) << "Invalid argument(s)"; - return -1; +bool MemMapping::MapFile(const std::string& fn) { + if (fn.empty()) { + LOG(ERROR) << "Empty filename"; + return false; } - *pMap = {}; - if (fn[0] == '@') { - if (sysMapBlockFile(fn + 1, pMap) != 0) { + // Block map file "@/cache/recovery/block.map". + if (!MapBlockFile(fn.substr(1))) { LOG(ERROR) << "Map of '" << fn << "' failed"; - return -1; + return false; } } else { // This is a regular file. - android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(fn, O_RDONLY))); + android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(fn.c_str(), O_RDONLY))); if (fd == -1) { PLOG(ERROR) << "Unable to open '" << fn << "'"; - return -1; + return false; } - if (!sysMapFD(fd, pMap)) { + if (!MapFD(fd)) { LOG(ERROR) << "Map of '" << fn << "' failed"; - return -1; + return false; } } - return 0; + return true; } -/* - * Release a memory mapping. - */ -void sysReleaseMap(MemMapping* pMap) { - std::for_each(pMap->ranges.cbegin(), pMap->ranges.cend(), [](const MappedRange& range) { +MemMapping::~MemMapping() { + for (const auto& range : ranges_) { if (munmap(range.addr, range.length) == -1) { - PLOG(ERROR) << "munmap(" << range.addr << ", " << range.length << ") failed"; + PLOG(ERROR) << "Failed to munmap(" << range.addr << ", " << range.length << ")"; } - }); - pMap->ranges.clear(); + }; + ranges_.clear(); } |