summary refs log tree commit diff stats
path: root/doc/pydoc/ranger.gui.widgets.titlebar.html
stat options
Period:
Authors:

Commits per author per week (path 'doc/pydoc/ranger.gui.widgets.titlebar.html')

AuthorW49 2024W50 2024W51 2024W52 2024Total
Total00000
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126
:(before "End Initialize Op Names")
put_new(Name, "cd", "software interrupt (int)");

:(before "End Single-Byte Opcodes")
case 0xcd: {  // int imm8 (software interrupt)
  trace(Callstack_depth+1, "run") << "syscall" << end();
  uint8_t code = next();
  if (code != 0x80) {
    raise << "Unimplemented interrupt code " << HEXBYTE << code << '\n' << end();
    raise << "  Only `int 80h` supported for now.\n" << end();
    break;
  }
  process_int80();
  break;
}

:(code)
void process_int80() {
  switch (Reg[EAX].u) {
  case 1:
    exit(/*exit code*/Reg[EBX].u);
    break;
  case 3:
    trace(Callstack_depth+1, "run") << "read: " << Reg[EBX].u << ' ' << Reg[ECX].u << ' ' << Reg[EDX].u << end();
    Reg[EAX].i = read(/*file descriptor*/Reg[EBX].u, /*memory buffer*/mem_addr_u8(Reg[ECX].u), /*size*/Reg[EDX].u);
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "read: " << strerror(errno) << '\n' << end();
    break;
  case 4:
    trace(Callstack_depth+1, "run") << "write: " << Reg[EBX].u << ' ' << Reg[ECX].u << ' ' << Reg[EDX].u << end();
    trace(Callstack_depth+1, "run") << Reg[ECX].u << " => " << mem_addr_string(Reg[ECX].u, Reg[EDX].u) << end();
    Reg[EAX].i = write(/*file descriptor*/Reg[EBX].u, /*memory buffer*/mem_addr_u8(Reg[ECX].u), /*size*/Reg[EDX].u);
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "write: " << strerror(errno) << '\n' << end();
    break;
  case 5: {
    check_flags(ECX);
    check_mode(EDX);
    trace(Callstack_depth+1, "run") << "open: " << Reg[EBX].u << ' ' << Reg[ECX].u << end();
    trace(Callstack_depth+1, "run") << Reg[EBX].u << " => " << mem_addr_kernel_string(Reg[EBX].u) << end();
    Reg[EAX].i = open(/*filename*/mem_addr_kernel_string(Reg[EBX].u), /*flags*/Reg[ECX].u, /*mode*/0640);
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "open: " << strerror(errno) << '\n' << end();
    break;
  }
  case 6:
    trace(Callstack_depth+1, "run") << "close: " << Reg[EBX].u << end();
    Reg[EAX].i = close(/*file descriptor*/Reg[EBX].u);
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "close: " << strerror(errno) << '\n' << end();
    break;
  case 8:
    check_mode(ECX);
    trace(Callstack_depth+1, "run") << "creat: " << Reg[EBX].u << end();
    trace(Callstack_depth+1, "run") << Reg[EBX].u << " => " << mem_addr_kernel_string(Reg[EBX].u) << end();
    Reg[EAX].i = creat(/*filename*/mem_addr_kernel_string(Reg[EBX].u), /*mode*/0640);
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "creat: " << strerror(errno) << '\n' << end();
    break;
  case 10:
    trace(Callstack_depth+1, "run") << "unlink: " << Reg[EBX].u << end();
    trace(Callstack_depth+1, "run") << Reg[EBX].u << " => " << mem_addr_kernel_string(Reg[EBX].u) << end();
    Reg[EAX].i = unlink(/*filename*/mem_addr_kernel_string(Reg[EBX].u));
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "unlink: " << strerror(errno) << '\n' << end();
    break;
  case 38:
    trace(Callstack_depth+1, "run") << "rename: " << Reg[EBX].u << " -> " << Reg[ECX].u << end();
    trace(Callstack_depth+1, "run") << Reg[EBX].u << " => " << mem_addr_kernel_string(Reg[EBX].u) << end();
    trace(Callstack_depth+1, "run") << Reg[ECX].u << " => " << mem_addr_kernel_string(Reg[ECX].u) << end();
    Reg[EAX].i = rename(/*old filename*/mem_addr_kernel_string(Reg[EBX].u), /*new filename*/mem_addr_kernel_string(Reg[ECX].u));
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].i << end();
    if (Reg[EAX].i == -1) raise << "rename: " << strerror(errno) << '\n' << end();
    break;
  case 90:  // mmap: allocate memory outside existing segment allocations
    trace(Callstack_depth+1, "run") << "mmap: allocate new segment" << end();
    // Ignore most arguments for now: address hint, protection flags, sharing flags, fd, offset.
    // We only support anonymous maps.
    Reg[EAX].u = new_segment(/*length*/read_mem_u32(Reg[EBX].u+0x4));
    trace(Callstack_depth+1, "run") << "result: " << Reg[EAX].u << end();
    break;
  case 0xa2:  // nanosleep
    cerr << "not sleeping\n";
    break;
  default:
    raise << HEXWORD << EIP << ": unimplemented syscall " << Reg[EAX].u << '\n' << end();
  }
}

// SubX is oblivious to file permissions, directories, symbolic links, terminals, and much else besides.
// Also ignoring any concurrency considerations for now.
void check_flags(int reg) {
  uint32_t flags = Reg[reg].u;
  if (flags != ((flags & O_RDONLY) | (flags & O_WRONLY))) {
    cerr << HEXWORD << EIP << ": most POSIX flags to the open() syscall are not supported. Just O_RDONLY and O_WRONLY for now. Zero concurrent access support.\n";
    exit(1);
  }
  if ((flags & O_RDONLY) && (flags & O_WRONLY)) {
    cerr << HEXWORD << EIP << ": can't open a file for both reading and writing at once. See http://man7.org/linux/man-pages/man2/open.2.html.\n";
    exit(1);
  }
}

void check_mode(int reg) {
  if (Reg[reg].u != 0600) {
    cerr << HEXWORD << EIP << ": SubX is oblivious to file permissions; register " << reg << " must be 0x180.\n";
    exit(1);
  }
}

:(before "End Globals")
// Very primitive/fixed/insecure mmap segments for now.
uint32_t Segments_allocated_above = END_HEAP;
:(code)
// always allocate multiples of the segment size
uint32_t new_segment(uint32_t length) {
  assert(length > 0);
  uint32_t result = (Segments_allocated_above - length) & 0xff000000;  // same number of zeroes as SEGMENT_ALIGNMENT
  if (result <= START_HEAP) {
    raise << "Allocated too many segments; the VM ran out of memory. "
          << "Maybe SEGMENT_ALIGNMENT can be smaller?\n" << die();
  }
  Mem.push_back(vma(result, result+length));
  Segments_allocated_above = result;
  return result;
}