user: Demonstrate the C code that generates the assembly output below:

```asm
<getvalue>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  mov    %rdi,%r12
  push   %rbp
  push   %rbx
  sub    $0x2c8,%rsp
  mov    %rsi,0x8(%rsp)
  xor    %esi,%esi
  lea    0xf0(%rsp),%rbp
  lea    0x10(%rsp),%r14
  mov    %rdx,(%rsp)
  lea    0xe8(%rsp),%rbx
  mov    %fs:0x28,%rax
  mov    %rax,0x2b8(%rsp)
  mov    D2(%rip),%rax
  mov    (%rax),%edx
  call   <fseek@plt>
  nopw   0x0(%rax,%rax,1)
L97:
  mov    %r12,%rdx
  mov    $0x1c4,%esi
  mov    %rbp,%rdi
  call   <fgets@plt>
  test   %rax,%rax
  je     L67
  mov    %rbp,%r15
  jmp    L222
  xchg   %ax,%ax
L4:
  add    $0x1,%r15
L222:
  movsbl (%r15),%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L4
  movsbl (%r15),%edi
  cmp    $0x23,%dil
  je     L97
  mov    %r14,%r13
  test   %dil,%dil
  je     L97
  nopl   0x0(%rax)
L143:
  cmp    $0x5f,%dil
  je     L84
  call   <isalnum@plt>
  test   %rax,%rax
  je     L158
L84:
  cmp    %rbx,%r13
  je     L248
  mov    %r13,%rdi
  mov    %r15,%rsi
  movsb  %ds:(%rsi),%es:(%rdi)
  mov    %rdi,%r13
  movsbl (%rsi),%edi
  mov    %rsi,%r15
  test   %dil,%dil
  jne    L143
  movb   $0x0,0x0(%r13)
  jmp    L97
  nopl   (%rax)
L158:
  movzbl (%r15),%eax
  movb   $0x0,0x0(%r13)
  cmp    $0x3d,%al
  je     L65
  nopl   (%rax)
L104:
  test   %al,%al
  je     L97
  movzbl 0x1(%r15),%eax
  add    $0x1,%r15
  cmp    $0x3d,%al
  jne    L104
L65:
  test   %al,%al
  je     L97
  nopl   (%rax)
L122:
  mov    %r15,%r13
  movsbl 0x1(%r15),%edi
  add    $0x1,%r15
  call   <isspace@plt>
  test   %rax,%rax
  jne    L122
  movzbl (%r15),%eax
  test   %al,%al
  je     L97
  cmp    $0x22,%al
  je     L34
L35:
  mov    (%rsp),%rdx
  lea    0xd8(%rdx),%rcx
  nopl   0x0(%rax)
L70:
  add    $0x1,%r15
  mov    %al,(%rdx)
  add    $0x1,%rdx
  movzbl (%r15),%eax
  test   %al,%al
  je     L46
  cmp    $0x22,%al
  je     L46
  cmp    %rdx,%rcx
  jne    L70
L248:
  mov    $0xfffffffd,%eax
L38:
  mov    0x2b8(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L170
  add    $0x2c8,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L34:
  movzbl 0x2(%r13),%eax
  lea    0x2(%r13),%r15
  test   %al,%al
  je     L116
  cmp    $0x22,%al
  jne    L35
L116:
  mov    (%rsp),%rdx
L46:
  movb   $0x0,(%rdx)
  mov    0x8(%rsp),%rdi
  mov    %r14,%rsi
  call   <strcmp@plt>
  test   %eax,%eax
  jne    L97
  jmp    L38
  nopl   0x0(%rax)
L67:
  mov    $0xfffffffe,%eax
  jmp    L38
L170:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int getvalue(FILE *conf, char const *key, char *value) {
  char readbuff[(2 * 216 + 20)];
  char keybuff[216];
  char *pb, *pkey, *pval;
  fseek(conf, 0L, SEEK_SET);
  while (NULL != fgets(readbuff, (2 * 216 + 20), conf)) {
    pb = readbuff;
    pkey = keybuff;
    pval = value;
    while (isspace(*pb))
      ++pb;
    if ('#' == *pb || '\0' == *pb)
      continue;
    while ('\0' != *pb && ('_' == *pb || isalnum(*pb))) {
      if (pkey >= keybuff + 216)
        return -3;
      *pkey++ = *pb++;
    }
    *pkey = '\0';
    while ('=' != *pb && '\0' != *pb)
      ++pb;
    if ('\0' == *pb)
      continue;
    while (isspace(*++pb))
      ;
    if ('\0' == *pb)
      continue;
    if ('"' == *pb)
      ++pb;
    while ('\0' != *pb && '"' != *pb) {
      if (pval >= value + 216)
        return -3;
      *pval++ = *pb++;
    }
    *pval = '\0';
    if (!strcmp(key, keybuff)) {
      return 0;
    }
  }
  return -2;
}
```