user: 请将以下的汇编代码转换成C语言代码:

```asm
<GrabGETVar>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x498,%rsp
  mov    %rdi,%rbp
  mov    %rsi,%r13
  mov    %rdx,%r14
  mov    %fs:0x28,%rax
  mov    %rax,0x488(%rsp)
  xor    %eax,%eax
  mov    $0x0,%ebx
  mov    $0x3f,%r12d
  jmp    L77
L69:
  mov    %dl,0x80(%rsp,%rbx,1)
  movb   $0x0,0x81(%rsp,%rbx,1)
  add    $0x1,%rbx
L77:
  mov    %rbp,%rdi
  call   <strlen@plt>
  cmp    %ebx,%eax
  jle    L12
  movzbl 0x0(%rbp,%rbx,1),%eax
  mov    %al,0x80(%rsp,%rbx,1)
  mov    %r12d,%edx
  cmp    $0x26,%al
  je     L69
  mov    %eax,%edx
  jmp    L69
L12:
  mov    $0x0,%r12d
  mov    $0x0,%ebp
  mov    $0x0,%ebx
  lea    0x80(%rsp),%r15
  jmp    L183
L158:
  cmp    $0x1,%ebp
  je     L19
  cmp    $0x2,%ebp
  jne    L118
L35:
  movslq %ebx,%rax
  movzbl 0x80(%rsp,%rax,1),%eax
  cmp    $0x3f,%al
  je     L156
  movslq %r12d,%rdx
  mov    %al,0x40(%rsp,%rdx,1)
  add    $0x1,%r12d
  movslq %r12d,%rax
  movb   $0x0,0x40(%rsp,%rax,1)
  mov    $0x2,%ebp
L118:
  add    $0x1,%ebx
L183:
  mov    %r15,%rdi
  call   <strlen@plt>
  cmp    %ebx,%eax
  jle    L48
  test   %ebp,%ebp
  jne    L158
  movslq %ebx,%rax
  cmpb   $0x3f,0x80(%rsp,%rax,1)
  jne    L118
  add    $0x1,%ebx
  mov    %ebp,%r12d
L19:
  movslq %ebx,%rax
  movzbl 0x80(%rsp,%rax,1),%eax
  cmp    $0x3d,%al
  je     L135
  movslq %r12d,%rdx
  mov    %al,(%rsp,%rdx,1)
  add    $0x1,%r12d
  movslq %r12d,%rax
  movb   $0x0,(%rsp,%rax,1)
  mov    $0x1,%ebp
  jmp    L118
L135:
  add    $0x1,%ebx
  mov    $0x0,%r12d
  jmp    L35
L156:
  mov    %rsp,%rdi
  mov    %r13,%rsi
  call   <IsEqual@plt>
  test   %rax,%rax
  jne    L152
  mov    $0x0,%r12d
  mov    $0x1,%ebp
  jmp    L118
L152:
  lea    0x40(%rsp),%rdi
  mov    $0x0,%edx
  mov    %r14,%rsi
  call   <CopyString@plt>
  mov    $0x1,%eax
  jmp    L193
L48:
  mov    %rsp,%rdi
  mov    %r13,%rsi
  call   <IsEqual@plt>
  mov    %rax,%rdx
  mov    $0xffffffff,%eax
  test   %rdx,%rdx
  jne    L27
L193:
  mov    0x488(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L150
  add    $0x498,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L27:
  lea    0x40(%rsp),%rdi
  mov    $0x0,%edx
  mov    %r14,%rsi
  call   <CopyString@plt>
  mov    $0x1,%eax
  jmp    L193
L150:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int GrabGETVar(char *getData, char *var, char *ret) {
  int i, v, n, c, nr;
  char AllVars[1024];
  char gVar[50];
  char gVal[50];
  c = 0;
  n = 0;
  for (i = 0; i < strlen(getData); i++) {
    if (getData[i] == '?') {
      c++;
      v = 1;
    }
    if (v == 1) {
      AllVars[n] = getData[i];
      if (getData[i] == '&') {
        c++;
        AllVars[n] = '?';
      }
      AllVars[n + 1] = 0x00;
      n++;
    }
  }
  n = 0;
  v = 0;
  for (i = 0; i < strlen(AllVars); i++) {
    if (v == 0) {
      if (AllVars[i] == '?') {
        n = 0;
        v = 1;
        i++;
      }
    }
    if (v == 1) {
      if (AllVars[i] == '=') {
        n = 0;
        v = 2;
        i++;
      } else {
        gVar[n] = AllVars[i];
        gVar[n + 1] = 0x00;
        n++;
      }
    }
    if (v == 2) {
      if (AllVars[i] == '?') {
        if (IsEqual(gVar, var)) {
          CopyString(gVal, ret, 0);
          return 1;
        }
        n = 0;
        v = 1;
      } else {
        gVal[n] = AllVars[i];
        gVal[n + 1] = 0x00;
        n++;
      }
    }
  }
  if (IsEqual(gVar, var)) {
    CopyString(gVal, ret, 0);
    return 1;
  }
  return -1;
}
```