Code analysis violations Bug in scheduler - race during with worker thread shutdown.
Showing the changes to src/vm/sys/fd_manager.cpp (1 of 18 files). Show all
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| 1 | // | ||
| 2 | // Dis VM | ||
| 3 | // File: fd_manager.cpp | ||
| 4 | // Author: arr | ||
| 5 | // | ||
| 6 | |||
| 7 | #include <array> | ||
| 8 | #include <mutex> | ||
| 9 | #include <unordered_map> | ||
| 10 | #include <exceptions.h> | ||
| 11 | #include <vm_memory.h> | ||
| 12 | #include "sys_utils.h" | ||
| 13 | |||
| 14 | using namespace disvm::runtime; | ||
| 15 | |||
| 16 | namespace | ||
| 17 | { | ||
| 18 | using fd_map_t = std::unordered_map<word_t, vm_alloc_t *>; | ||
| 19 | |||
| 20 | auto std_fd = std::array<vm_alloc_t * , 3> | ||
| 21 | { | ||
| 22 | nullptr, // stdin | ||
| 23 | nullptr, // stdout | ||
| 24 | nullptr, // stderr | ||
| 25 | }; | ||
| 26 | |||
| 27 | auto next_fd = word_t{ 0 }; | ||
| 28 | |||
| 29 | std::mutex fd_map_lock; | ||
| 30 | auto fd_map = fd_map_t{}; | ||
| 31 | } | ||
| 32 | |||
| 33 | word_t disvm::runtime::sys::create_fd_record(vm_alloc_t * fd_alloc) | ||
| 34 | { | ||
| 35 | assert(fd_alloc != nullptr); | ||
| 36 | |||
| 37 | { | ||
| 38 | std::lock_guard<std::mutex> lock{ fd_map_lock }; | ||
| 39 | |||
| 40 | auto new_fd = next_fd; | ||
| 41 | next_fd++; | ||
| 42 | if (new_fd < static_cast<word_t>(std_fd.size())) | ||
| 43 | { | ||
| 44 | std_fd[new_fd] = fd_alloc; | ||
| 45 | } | ||
| 46 | else | ||
| 47 | { | ||
| 48 | assert(fd_map.cend() == fd_map.find(new_fd)); | ||
| 49 | fd_map[new_fd] = fd_alloc; | ||
| 50 | } | ||
| 51 | |||
| 52 | return new_fd; | ||
| 53 | } | ||
| 54 | } | ||
| 55 | |||
| 56 | vm_alloc_t * disvm::runtime::sys::fetch_fd_record(word_t fd) | ||
| 57 | { | ||
| 58 | assert(fd != sys::vm_invalid_fd && "Invalid FD value"); | ||
| 59 | |||
| 60 | if (0 <= fd && fd < static_cast<word_t>(std_fd.size())) | ||
| 61 | return std_fd[fd]; | ||
| 62 | |||
| 63 | { | ||
| 64 | std::lock_guard<std::mutex> lock{ fd_map_lock }; | ||
| 65 | auto iter = fd_map.find(fd); | ||
| 66 | if (iter == fd_map.cend()) | ||
| 67 | throw vm_user_exception{ "Unknown file descriptor" }; | ||
| 68 | |||
| 69 | return iter->second; | ||
| 70 | } | ||
| 71 | } | ||
| 72 | |||
| 73 | void disvm::runtime::sys::drop_fd_record(word_t fd) | ||
| 74 | { | ||
| 75 | assert(fd != sys::vm_invalid_fd && "Invalid FD value"); | ||
| 76 | assert(fd >= static_cast<word_t>(std_fd.size()) && "Request to drop std file?"); | ||
| 77 | |||
| 78 | { | ||
| 79 | std::lock_guard<std::mutex> lock{ fd_map_lock }; | ||
| 80 | auto iter = fd_map.find(fd); | ||
| 81 | if (iter != fd_map.cend()) | ||
| 82 | fd_map.erase(iter); | ||
| 83 | } | ||
| 84 | } | ||