user: What is the c source code of the assembly code below?

```asm
<zconfig_split_nameval>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x38(%rbp)
  mov    %rsi,-0x40(%rbp)
  mov    %rdx,-0x48(%rbp)
  mov    -0x38(%rbp),%rax
  mov    %rax,-0x20(%rbp)
  jmp    L154
L153:
  addq   $0x1,-0x20(%rbp)
L154:
  mov    -0x20(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L57
  mov    -0x20(%rbp),%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L153
L57:
  mov    -0x20(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  jne    L195
  mov    $0xffffffff,%eax
  jmp    L92
L195:
  mov    -0x20(%rbp),%rax
  mov    %rax,-0x8(%rbp)
  jmp    L60
L138:
  addq   $0x1,-0x8(%rbp)
L60:
  mov    -0x8(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L10
  mov    -0x8(%rbp),%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L10
  mov    -0x8(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x3d,%al
  jne    L138
L10:
  mov    -0x8(%rbp),%rax
  mov    %rax,-0x10(%rbp)
  jmp    L0
L4:
  addq   $0x1,-0x10(%rbp)
L0:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L193
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L4
L193:
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  cmp    $0x3d,%al
  je     L78
  mov    $0xfffffffe,%eax
  jmp    L92
L78:
  mov    -0x8(%rbp),%rax
  movb   $0x0,(%rax)
  mov    -0x40(%rbp),%rax
  mov    -0x20(%rbp),%rdx
  mov    %rdx,(%rax)
  addq   $0x1,-0x10(%rbp)
  mov    -0x10(%rbp),%rax
  mov    %rax,-0x18(%rbp)
  jmp    L77
L152:
  addq   $0x1,-0x18(%rbp)
L77:
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  test   %al,%al
  je     L23
  mov    -0x18(%rbp),%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L152
L23:
  mov    -0x18(%rbp),%rax
  mov    %rax,%rdi
  call   <strlen@plt>
  mov    %eax,-0x24(%rbp)
  mov    -0x24(%rbp),%eax
  cltq
  lea    -0x1(%rax),%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x20(%rbp)
  jmp    L38
L32:
  mov    -0x20(%rbp),%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  je     L96
  mov    -0x20(%rbp),%rax
  movb   $0x0,(%rax)
  subq   $0x1,-0x20(%rbp)
L38:
  mov    -0x20(%rbp),%rax
  cmp    -0x18(%rbp),%rax
  jae    L32
  jmp    L196
L96:
  nop
L196:
  mov    -0x48(%rbp),%rax
  mov    -0x18(%rbp),%rdx
  mov    %rdx,(%rax)
  mov    $0x0,%eax
L92:
  leave
  ret
```

assistant: ```c
int zconfig_split_nameval(char *buf, char **name, char **value) {
  char *np, *vp, *cp, *ep;
  int len;
  for (np = buf; *np && (isspace(*np)); np++)
    ;
  ;
  if (*np == 0) {
    return (-1);
  }
  for (ep = np; *ep && ((!isspace(*ep) && *ep != '=')); ep++)
    ;
  ;
  for (cp = ep; *cp && (isspace(*cp)); cp++)
    ;
  ;
  if (*cp != '=') {
    return (-2);
  }
  *ep = 0;
  *name = np;
  cp++;
  for (vp = cp; *vp && (isspace(*vp)); vp++)
    ;
  ;
  len = strlen(vp);
  np = vp + (len - 1);
  while (np >= vp) {
    if (isspace(*np)) {
      *np = 0;
      np--;
    } else {
      break;
    }
  }
  *value = vp;
  return 0;
}
```