user: What would the C source look like for the assembly code provided here?

```asm
<Mx1_rewrap>:
  endbr64
  push   %r15
  push   %r14
  mov    %r8,%r14
  push   %r13
  mov    %r9,%r13
  push   %r12
  mov    %rsi,%r12
  push   %rbp
  push   %rbx
  sub    $0x138,%rsp
  mov    (%rsi),%r10
  mov    $0x7d,%esi
  mov    (%rdx),%rbx
  mov    %rdi,0x18(%rsp)
  mov    0x170(%rsp),%r15
  mov    %rdx,0x10(%rsp)
  mov    %r10,%rdi
  mov    %rcx,0x8(%rsp)
  mov    %fs:0x28,%rax
  mov    %rax,0x128(%rsp)
  xor    %eax,%eax
  mov    %r10,(%rsp)
  call   <strchr@plt>
  mov    (%rsp),%r10
  test   %rax,%rax
  je     L82
  mov    %rax,%rbp
  sub    %r10,%rbp
  testb  $0x2,0x178(%rsp)
  jne    L89
  movslq %ebp,%r14
  movslq %ebp,%rdx
  test   %ebp,%ebp
  jg     L49
L54:
  mov    %rbx,%rax
  sub    0x8(%rsp),%rax
  mov    %r13,%rdi
  add    %rdx,%rax
  mov    %rax,(%rsp)
  call   <strlen@plt>
  mov    %r15,%rdi
  cltq
  add    (%rsp),%rax
  mov    %rax,(%rsp)
  call   <strlen@plt>
  cltq
  add    (%rsp),%rax
  cmp    $0xff,%rax
  jg     L104
  mov    %rbx,%rdi
  mov    %r13,%rsi
  call   <strcpy@plt>
  mov    %r13,%rdi
  call   <strlen@plt>
  cltq
  add    %rax,%rbx
  test   %r14d,%r14d
  jle    L96
  lea    0x20(%rsp),%rsi
  mov    %r14d,%edx
  mov    %rbx,%rdi
  call   <strncpy@plt>
L96:
  add    %r14,%rbx
  mov    %r15,%rsi
  mov    %rbx,%rdi
  call   <strcpy@plt>
  mov    %r15,%rdi
  call   <strlen@plt>
  add    %rbp,(%r12)
  cltq
  add    %rax,%rbx
  mov    0x10(%rsp),%rax
  mov    %rbx,(%rax)
  mov    $0x1,%eax
L80:
  mov    0x128(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L5
  add    $0x138,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L49:
  lea    0x20(%rsp),%r14
  mov    0x18(%rsp),%rdi
  xor    %ecx,%ecx
  mov    %ebp,%r8d
  mov    $0x1,%r9d
  mov    %r14,%rdx
  mov    %r10,%rsi
  call   <Mx1_substitute@plt>
  test   %eax,%eax
  jle    L80
  mov    %r14,%rdi
  call   <strlen@plt>
  movslq %eax,%rdx
  mov    %rdx,%r14
  jmp    L54
  nopw   0x0(%rax,%rax,1)
L89:
  xor    %edx,%edx
  xor    %r14d,%r14d
  jmp    L54
L104:
  mov    0x18(%rsp),%rdi
  xor    %edx,%edx
  lea    D13(%rip),%rsi
  call   <Mx1_report_error@plt>
  mov    $0xffffffff,%eax
  jmp    L80
L82:
  lea    0x20(%rsp),%rbp
  mov    %r14,%rdx
  lea    D9(%rip),%rsi
  mov    %rbp,%rdi
  call   <sprintf@plt>
  mov    0x18(%rsp),%rdi
  xor    %edx,%edx
  mov    %rbp,%rsi
  call   <Mx1_report_error@plt>
  mov    $0xffffffff,%eax
  jmp    L80
L5:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: disassemble_data
arguments: tag: D13
type: string
name: disassemble_data
arguments: tag: D9
type: string

tool: D13: Line length overflow while text substitution

tool: D9: No closing bracket found for '%s'

assistant: ```c
int Mx1_rewrap(struct Mx1 *m, char **read_pt, char **write_pt, char *write_base, char *envelope, char *front, char *back, int flag) {
  char *rpt, *wpt, *ept, content[256], msg[256];
  int l, ret;
  rpt = *read_pt;
  wpt = *write_pt;
  ept = strchr(rpt, '}');
  if (ept == NULL) {
    sprintf(msg, "No closing bracket found for '%s'", envelope);
    Mx1_report_error(m, msg, 0);
    return (-1);
  }
  l = ept - rpt;
  if (flag & 2)
    l = 0;
  if (l > 0) {
    ret = Mx1_substitute(m, rpt, content, 0, l, 1);
    if (ret <= 0)
      return (ret);
    l = strlen(content);
  }
  if ((wpt - write_base) + l + strlen(front) + strlen(back) > 255) {
    Mx1_report_error(m, "Line length overflow while text substitution", 0);
    return (-1);
  }
  strcpy(wpt, front);
  wpt += strlen(front);
  if (l > 0)
    strncpy(wpt, content, l);
  wpt += l;
  strcpy(wpt, back);
  wpt += strlen(back);
  (*read_pt) += ept - rpt;
  (*write_pt) = wpt;
  return (1);
}
```