user: 请从给定的汇编指令推导出C源代码:

```asm
<readgrey>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %rdi,%r13
  mov    %rsi,0x8(%rsp)
  mov    %rdx,%rbp
  mov    %rcx,%rbx
  mov    %fs:0x28,%rax
  mov    %rax,0x18(%rsp)
  xor    %eax,%eax
  movl   $0x0,0x14(%rsp)
  lea    0x14(%rsp),%rcx
  mov    %rbx,%rdx
  mov    %rbp,%rsi
  call   <readDIMs@plt>
  test   %rax,%rax
  jne    L66
  lea    D5(%rip),%rdi
  call   <puts@plt>
  mov    0x14(%rsp),%ecx
  mov    (%rbx),%edx
  mov    0x0(%rbp),%esi
  lea    D13(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    0x0(%rbp),%edx
  test   %edx,%edx
  jle    L48
  mov    (%rbx),%eax
  test   %eax,%eax
  jle    L47
  imul   %eax,%edx
  mov    %edx,%ebx
  mov    %edx,0x4(%rsp)
  mov    %edx,%edi
  call   <malloc@plt>
  mov    %rax,%r12
  mov    %ebx,%esi
  lea    D11(%rip),%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  test   %r12,%r12
  je     L113
  mov    0x4(%rsp),%ebx
  mov    %ebx,%edx
  mov    $0x0,%esi
  mov    %r12,%rdi
  call   <memset@plt>
  movb   $0x0,0x13(%rsp)
  mov    %ebx,%r15d
  mov    $0x0,%ebx
  lea    D36(%rip),%r14
  jmp    L97
L66:
  lea    D15(%rip),%rdi
  call   <puts@plt>
  movl   $0xffffffff,0x4(%rsp)
  jmp    L30
L48:
  lea    D42(%rip),%rdi
  call   <puts@plt>
  movl   $0xffffffff,0x4(%rsp)
  jmp    L30
L47:
  lea    D68(%rip),%rdi
  call   <puts@plt>
  movl   $0xffffffff,0x4(%rsp)
  jmp    L30
L113:
  lea    D40(%rip),%rdi
  call   <puts@plt>
  movl   $0xffffffff,0x4(%rsp)
  jmp    L30
L79:
  movsbl 0x13(%rsp),%edx
  mov    %ebp,%esi
  mov    %r14,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  movzbl 0x13(%rsp),%eax
  mov    %al,(%r12,%rbx,1)
  add    $0x1,%rbx
  cmp    %r15,%rbx
  je     L67
L97:
  mov    %ebx,%ebp
  lea    0x13(%rsp),%rdi
  mov    %r13,%rcx
  mov    $0x1,%edx
  mov    $0x1,%esi
  call   <fread@plt>
  movsbl 0x13(%rsp),%edi
  call   <isprint@plt>
  mov    $0x2e,%ecx
  test   %rax,%rax
  je     L79
  movsbl 0x13(%rsp),%ecx
  jmp    L79
L67:
  mov    0x8(%rsp),%rax
  mov    %r12,(%rax)
L30:
  mov    0x18(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L55
  mov    0x4(%rsp),%eax
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L55:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: unpack_data
arguments: label: D5
type_infered: string
name: unpack_data
arguments: label: D13
type_infered: string
name: unpack_data
arguments: label: D11
type_infered: string
name: unpack_data
arguments: label: D36
type_infered: string
name: unpack_data
arguments: label: D15
type_infered: string
name: unpack_data
arguments: label: D42
type_infered: string
name: unpack_data
arguments: label: D68
type_infered: string
name: unpack_data
arguments: label: D40
type_infered: string

tool: D5: read grey

tool: D13: w:%d h:%d i:%d


tool: D11: arraysze:%d


tool: D36: DBG: Idx = %d, char = (%02x) %c


tool: D15: could not read DIMS

tool: D42: Invalid width

tool: D68: Invalid height

tool: D40: Failed to allocate memory, Possibly out of memory

assistant: ```c
int readgrey(FILE *imgfile, char **image_data, int *width, int *height) {
  int intensity = 0;
  int arraysze = 0;
  char *imagedata = NULL;
  if (readDIMs(imgfile, width, height, &intensity) != 0) {
    printf("could not read DIMS\n");
    return -1;
  }
  printf("read grey\n");
  printf("w:%d h:%d i:%d\n", *width, *height, intensity);
  if (*width < 1) {
    printf("Invalid width\n");
    return -1;
  }
  if (*height < 1) {
    printf("Invalid height\n");
    return -1;
  }
  arraysze = (*width) * (*height);
  imagedata = (char *)malloc(sizeof(char) * arraysze);
  printf("arraysze:%d\n", arraysze);
  if (imagedata == NULL) {
    printf("Failed to allocate memory, Possibly out of memory\n");
    return -1;
  }
  memset(imagedata, 0, sizeof(char) * arraysze);
  {
    int idxrd = 0;
    char c = 0;
    for (; idxrd < arraysze; ++idxrd) {
      fread(&c, 1, 1, imgfile);
      printf("DBG: Idx = %d, char = (%02x) %c\n", idxrd, c, (isprint(c) ? c : '.'));
      imagedata[idxrd] = c;
    }
  }
  *image_data = imagedata;
  return arraysze;
}
```