diff options
Diffstat (limited to 'lib/Support/Unix')
-rw-r--r-- | lib/Support/Unix/PathV2.inc | 78 | ||||
-rw-r--r-- | lib/Support/Unix/Signals.inc | 50 |
2 files changed, 112 insertions, 16 deletions
diff --git a/lib/Support/Unix/PathV2.inc b/lib/Support/Unix/PathV2.inc index 4e71b42be9..62d9a2fb07 100644 --- a/lib/Support/Unix/PathV2.inc +++ b/lib/Support/Unix/PathV2.inc @@ -24,6 +24,9 @@ #if HAVE_FCNTL_H #include <fcntl.h> #endif +#ifdef HAVE_SYS_MMAN_H +#include <sys/mman.h> +#endif #if HAVE_DIRENT_H # include <dirent.h> # define NAMLEN(dirent) strlen((dirent)->d_name) @@ -351,20 +354,22 @@ error_code status(const Twine &path, file_status &result) { return ec; } + perms prms = static_cast<perms>(status.st_mode & perms_mask); + if (S_ISDIR(status.st_mode)) - result = file_status(file_type::directory_file); + result = file_status(file_type::directory_file, prms); else if (S_ISREG(status.st_mode)) - result = file_status(file_type::regular_file); + result = file_status(file_type::regular_file, prms); else if (S_ISBLK(status.st_mode)) - result = file_status(file_type::block_file); + result = file_status(file_type::block_file, prms); else if (S_ISCHR(status.st_mode)) - result = file_status(file_type::character_file); + result = file_status(file_type::character_file, prms); else if (S_ISFIFO(status.st_mode)) - result = file_status(file_type::fifo_file); + result = file_status(file_type::fifo_file, prms); else if (S_ISSOCK(status.st_mode)) - result = file_status(file_type::socket_file); + result = file_status(file_type::socket_file, prms); else - result = file_status(file_type::type_unknown); + result = file_status(file_type::type_unknown, prms); result.fs_st_dev = status.st_dev; result.fs_st_ino = status.st_ino; @@ -372,6 +377,35 @@ error_code status(const Twine &path, file_status &result) { return error_code::success(); } +// Modifies permissions on a file. +error_code permissions(const Twine &path, perms prms) { + if ((prms & add_perms) && (prms & remove_perms)) + llvm_unreachable("add_perms and remove_perms are mutually exclusive"); + + // Get current permissions + file_status info; + if (error_code ec = status(path, info)) { + return ec; + } + + // Set updated permissions. + SmallString<128> path_storage; + StringRef p = path.toNullTerminatedStringRef(path_storage); + perms permsToSet; + if (prms & add_perms) { + permsToSet = (info.permissions() | prms) & perms_mask; + } else if (prms & remove_perms) { + permsToSet = (info.permissions() & ~prms) & perms_mask; + } else { + permsToSet = prms & perms_mask; + } + if (::chmod(p.begin(), static_cast<mode_t>(permsToSet))) { + return error_code(errno, system_category()); + } + + return error_code::success(); +} + // Since this is most often used for temporary files, mode defaults to 0600. error_code unique_file(const Twine &model, int &result_fd, SmallVectorImpl<char> &result_path, @@ -525,6 +559,36 @@ error_code get_magic(const Twine &path, uint32_t len, return error_code::success(); } +error_code map_file_pages(const Twine &path, off_t file_offset, size_t size, + bool map_writable, void *&result) { + SmallString<128> path_storage; + StringRef name = path.toNullTerminatedStringRef(path_storage); + int oflags = map_writable ? O_RDWR : O_RDONLY; + int ofd = ::open(name.begin(), oflags); + if ( ofd == -1 ) + return error_code(errno, system_category()); + AutoFD fd(ofd); + int flags = map_writable ? MAP_SHARED : MAP_PRIVATE; + int prot = map_writable ? (PROT_READ|PROT_WRITE) : PROT_READ; +#ifdef MAP_FILE + flags |= MAP_FILE; +#endif + result = ::mmap(0, size, prot, flags, fd, file_offset); + if (result == MAP_FAILED) { + return error_code(errno, system_category()); + } + + return error_code::success(); +} + +error_code unmap_file_pages(void *base, size_t size) { + if ( ::munmap(base, size) == -1 ) + return error_code(errno, system_category()); + + return error_code::success(); +} + + } // end namespace fs } // end namespace sys } // end namespace llvm diff --git a/lib/Support/Unix/Signals.inc b/lib/Support/Unix/Signals.inc index 130b11b93d..35f01802ba 100644 --- a/lib/Support/Unix/Signals.inc +++ b/lib/Support/Unix/Signals.inc @@ -15,6 +15,7 @@ #include "Unix.h" #include "llvm/ADT/STLExtras.h" #include "llvm/Support/Mutex.h" +#include <string> #include <vector> #include <algorithm> #if HAVE_EXECINFO_H @@ -43,7 +44,7 @@ static SmartMutex<true> SignalsMutex; /// InterruptFunction - The function to call if ctrl-c is pressed. static void (*InterruptFunction)() = 0; -static std::vector<sys::Path> FilesToRemove; +static std::vector<std::string> FilesToRemove; static std::vector<std::pair<void(*)(void*), void*> > CallBacksToRun; // IntSigs - Signals that may interrupt the program at any time. @@ -121,10 +122,20 @@ static void UnregisterHandlers() { /// RemoveFilesToRemove - Process the FilesToRemove list. This function /// should be called with the SignalsMutex lock held. +/// NB: This must be an async signal safe function. It cannot allocate or free +/// memory, even in debug builds. static void RemoveFilesToRemove() { - while (!FilesToRemove.empty()) { - FilesToRemove.back().eraseFromDisk(true); - FilesToRemove.pop_back(); + // Note: avoid iterators in case of debug iterators that allocate or release + // memory. + for (unsigned i = 0, e = FilesToRemove.size(); i != e; ++i) { + // Note that we don't want to use any external code here, and we don't care + // about errors. We're going to try as hard as we can as often as we need + // to to make these files go away. If these aren't files, too bad. + // + // We do however rely on a std::string implementation for which repeated + // calls to 'c_str()' don't allocate memory. We pre-call 'c_str()' on all + // of these strings to try to ensure this is safe. + unlink(FilesToRemove[i].c_str()); } } @@ -184,7 +195,19 @@ void llvm::sys::SetInterruptFunction(void (*IF)()) { bool llvm::sys::RemoveFileOnSignal(const sys::Path &Filename, std::string* ErrMsg) { SignalsMutex.acquire(); - FilesToRemove.push_back(Filename); + std::string *OldPtr = FilesToRemove.empty() ? 0 : &FilesToRemove[0]; + FilesToRemove.push_back(Filename.str()); + + // We want to call 'c_str()' on every std::string in this vector so that if + // the underlying implementation requires a re-allocation, it happens here + // rather than inside of the signal handler. If we see the vector grow, we + // have to call it on every entry. If it remains in place, we only need to + // call it on the latest one. + if (OldPtr == &FilesToRemove[0]) + FilesToRemove.back().c_str(); + else + for (unsigned i = 0, e = FilesToRemove.size(); i != e; ++i) + FilesToRemove[i].c_str(); SignalsMutex.release(); @@ -195,10 +218,19 @@ bool llvm::sys::RemoveFileOnSignal(const sys::Path &Filename, // DontRemoveFileOnSignal - The public API void llvm::sys::DontRemoveFileOnSignal(const sys::Path &Filename) { SignalsMutex.acquire(); - std::vector<sys::Path>::reverse_iterator I = - std::find(FilesToRemove.rbegin(), FilesToRemove.rend(), Filename); - if (I != FilesToRemove.rend()) - FilesToRemove.erase(I.base()-1); + std::vector<std::string>::reverse_iterator RI = + std::find(FilesToRemove.rbegin(), FilesToRemove.rend(), Filename.str()); + std::vector<std::string>::iterator I = FilesToRemove.end(); + if (RI != FilesToRemove.rend()) + I = FilesToRemove.erase(RI.base()-1); + + // We need to call c_str() on every element which would have been moved by + // the erase. These elements, in a C++98 implementation where c_str() + // requires a reallocation on the first call may have had the call to c_str() + // made on insertion become invalid by being copied down an element. + for (std::vector<std::string>::iterator E = FilesToRemove.end(); I != E; ++I) + I->c_str(); + SignalsMutex.release(); } |