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

```asm
<httpdate_to_timet>:
  endbr64
  push   %r15
  mov    $0x28,%edx
  xor    %esi,%esi
  push   %r14
  push   %r13
  mov    %rdi,%r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x488,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x478(%rsp)
  xor    %eax,%eax
  lea    0x50(%rsp),%rax
  mov    %rax,%rdi
  mov    %rax,0x10(%rsp)
  call   <memset@plt>
  movzbl 0x0(%r13),%eax
  cmp    $0x9,%al
  je     L263
  cmp    $0x20,%al
  jne    L100
  nopl   0x0(%rax)
L263:
  movzbl 0x1(%r13),%eax
  add    $0x1,%r13
  cmp    $0x20,%al
  je     L263
  cmp    $0x9,%al
  je     L263
L100:
  lea    0x2c(%rsp),%r14
  lea    0x34(%rsp),%r12
  mov    %r13,%rdi
  lea    0x3c(%rsp),%r15
  lea    0x80(%rsp),%rbp
  mov    %r12,%r9
  lea    0x38(%rsp),%rbx
  push   %r14
  mov    %r15,%r8
  mov    %rbp,%rcx
  mov    %rbx,%rdx
  lea    D2(%rip),%rsi
  lea    0x38(%rsp),%rax
  mov    %rax,0x10(%rsp)
  push   %rax
  xor    %eax,%eax
  call   <sscanf@plt>
  pop    %r10
  pop    %r11
  cmp    $0x6,%eax
  je     L313
L311:
  push   %r14
  mov    %r12,%r9
  mov    %r15,%r8
  mov    %rbp,%rcx
  push   0x10(%rsp)
  mov    %rbx,%rdx
  lea    D41(%rip),%rsi
  xor    %eax,%eax
  mov    %r13,%rdi
  call   <sscanf@plt>
  pop    %r8
  pop    %r9
  cmp    $0x6,%eax
  je     L161
L12:
  push   %r15
  lea    D50(%rip),%rsi
  mov    %r13,%rdi
  mov    %rbx,%r9
  push   %rbp
  mov    0x18(%rsp),%rcx
  mov    %r14,%r8
  mov    %r12,%rdx
  xor    %eax,%eax
  call   <sscanf@plt>
  pop    %rsi
  pop    %rdi
  cmp    $0x6,%eax
  je     L268
L303:
  push   %r15
  mov    %r12,%rdx
  mov    %rbx,%r9
  mov    %r14,%r8
  push   %rbp
  mov    0x18(%rsp),%rcx
  lea    D17(%rip),%rsi
  mov    %r13,%rdi
  xor    %eax,%eax
  call   <sscanf@plt>
  pop    %rdx
  pop    %rcx
  cmp    $0x6,%eax
  je     L136
L207:
  lea    0x280(%rsp),%r11
  xor    %eax,%eax
  mov    %r15,%r9
  mov    %rbp,%r8
  sub    $0x8,%rsp
  mov    %r11,%rdx
  mov    %rbx,%rcx
  mov    %r13,%rdi
  push   %r14
  lea    D67(%rip),%rsi
  push   0x18(%rsp)
  push   %r12
  mov    %r11,0x38(%rsp)
  call   <sscanf@plt>
  add    $0x20,%rsp
  mov    0x18(%rsp),%r11
  cmp    $0x7,%eax
  je     L73
L175:
  sub    $0x8,%rsp
  mov    %r11,%rdx
  xor    %eax,%eax
  mov    %r15,%r9
  push   %r14
  mov    %rbp,%r8
  mov    %rbx,%rcx
  lea    D0(%rip),%rsi
  push   0x18(%rsp)
  mov    %r13,%rdi
  push   %r12
  mov    %r11,0x38(%rsp)
  call   <sscanf@plt>
  add    $0x20,%rsp
  mov    0x18(%rsp),%r11
  cmp    $0x7,%eax
  je     L82
L3:
  sub    $0x8,%rsp
  mov    %r11,%rdx
  xor    %eax,%eax
  mov    %r12,%r9
  push   %r15
  mov    %rbx,%r8
  mov    %rbp,%rcx
  lea    D13(%rip),%rsi
  push   %r14
  mov    %r13,%rdi
  push   0x20(%rsp)
  mov    %r11,0x28(%rsp)
  call   <sscanf@plt>
  add    $0x20,%rsp
  mov    0x8(%rsp),%r11
  cmp    $0x7,%eax
  jne    L104
  lea    0x48(%rsp),%rsi
  mov    %r11,%rdi
  call   <scan_wday@plt>
  test   %rax,%rax
  je     L104
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  test   %rax,%rax
  je     L104
  mov    0x48(%rsp),%rax
  movd   0x30(%rsp),%xmm1
  movd   0x2c(%rsp),%xmm2
  movd   0x34(%rsp),%xmm3
  mov    %rax,0x70(%rsp)
  mov    0x40(%rsp),%rax
  punpckldq %xmm2,%xmm1
  mov    %rax,0x58(%rsp)
  mov    0x38(%rsp),%eax
  mov    %eax,0x50(%rsp)
  mov    0x3c(%rsp),%eax
  movd   %eax,%xmm0
  punpckldq %xmm3,%xmm0
  punpcklqdq %xmm1,%xmm0
  movaps %xmm0,0x60(%rsp)
L202:
  cmp    $0x76c,%eax
  jle    L246
L57:
  sub    $0x76c,%eax
  mov    %eax,0x60(%rsp)
L114:
  mov    0x10(%rsp),%rdi
  call   <tm_to_time@plt>
L76:
  mov    0x478(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L244
  add    $0x488,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L268:
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  test   %rax,%rax
  je     L303
L47:
  mov    0x38(%rsp),%eax
  movd   0x30(%rsp),%xmm1
  movd   0x2c(%rsp),%xmm6
  movd   0x34(%rsp),%xmm7
  mov    %eax,0x50(%rsp)
  mov    0x40(%rsp),%rax
  punpckldq %xmm6,%xmm1
  mov    %rax,0x58(%rsp)
  mov    0x3c(%rsp),%eax
  movd   %eax,%xmm0
  punpckldq %xmm7,%xmm0
  punpcklqdq %xmm1,%xmm0
  movaps %xmm0,0x60(%rsp)
  cmp    $0x76c,%eax
  jg     L57
L246:
  cmp    $0x45,%eax
  jg     L114
  add    $0x64,%eax
  mov    %eax,0x60(%rsp)
  jmp    L114
  nopl   0x0(%rax,%rax,1)
L313:
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  test   %rax,%rax
  je     L311
L41:
  mov    0x38(%rsp),%eax
  movd   0x30(%rsp),%xmm1
  movd   0x2c(%rsp),%xmm4
  movd   0x34(%rsp),%xmm5
  mov    %eax,0x50(%rsp)
  mov    0x40(%rsp),%rax
  punpckldq %xmm4,%xmm1
  mov    %rax,0x58(%rsp)
  mov    0x3c(%rsp),%eax
  movd   %eax,%xmm0
  punpckldq %xmm5,%xmm0
  punpcklqdq %xmm1,%xmm0
  movaps %xmm0,0x60(%rsp)
  jmp    L202
L161:
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  test   %rax,%rax
  je     L12
  jmp    L47
  nopl   0x0(%rax,%rax,1)
L136:
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  test   %rax,%rax
  je     L207
  jmp    L41
  nopl   0x0(%rax,%rax,1)
L73:
  mov    %r11,%rdi
  lea    0x48(%rsp),%rsi
  call   <scan_wday@plt>
  mov    0x18(%rsp),%r11
  test   %rax,%rax
  je     L175
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  mov    0x18(%rsp),%r11
  test   %rax,%rax
  je     L175
  mov    0x48(%rsp),%rax
  mov    %rax,0x70(%rsp)
  jmp    L47
  nopl   (%rax)
L82:
  mov    %r11,%rdi
  lea    0x48(%rsp),%rsi
  call   <scan_wday@plt>
  mov    0x18(%rsp),%r11
  test   %rax,%rax
  je     L3
  lea    0x40(%rsp),%rsi
  mov    %rbp,%rdi
  call   <scan_mon@plt>
  mov    0x18(%rsp),%r11
  test   %rax,%rax
  je     L3
  mov    0x48(%rsp),%rax
  mov    %rax,0x70(%rsp)
  jmp    L41
L104:
  mov    $0xffffffff,%eax
  jmp    L76
L244:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: read_data
arguments: tag: D2
type_guessed: string
name: read_data
arguments: tag: D41
type_guessed: string
name: read_data
arguments: tag: D50
type_guessed: string
name: read_data
arguments: tag: D17
type_guessed: string
name: read_data
arguments: tag: D67
type_guessed: string
name: read_data
arguments: tag: D0
type_guessed: string
name: read_data
arguments: tag: D13
type_guessed: string

tool: D2: %d-%[a-zA-Z]-%d %d:%d:%d GMT

tool: D41: %d %[a-zA-Z] %d %d:%d:%d GMT

tool: D50: %d:%d:%d GMT %d-%[a-zA-Z]-%d

tool: D17: %d:%d:%d GMT %d %[a-zA-Z] %d

tool: D67: %[a-zA-Z], %d-%[a-zA-Z]-%d %d:%d:%d GMT

tool: D0: %[a-zA-Z], %d %[a-zA-Z] %d %d:%d:%d GMT

tool: D13: %[a-zA-Z] %[a-zA-Z] %d %d:%d:%d GMT %d

assistant: ```c
time_t httpdate_to_timet(const char *str) {
  struct tm tm;
  const char *cp;
  char str_mon[500], str_wday[500];
  int tm_sec, tm_min, tm_hour, tm_mday, tm_year;
  long tm_mon, tm_wday;
  time_t t;
  memset((char *)&tm, 0, sizeof(struct tm));
  for (cp = str; *cp == ' ' || *cp == '\t'; ++cp)
    ;
  if (sscanf(cp, "%d-%[a-zA-Z]-%d %d:%d:%d GMT", &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, &tm_sec) == 6 && scan_mon(str_mon, &tm_mon)) {
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
  } else if (sscanf(cp, "%d %[a-zA-Z] %d %d:%d:%d GMT", &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, &tm_sec) == 6 && scan_mon(str_mon, &tm_mon)) {
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
  } else if (sscanf(cp, "%d:%d:%d GMT %d-%[a-zA-Z]-%d", &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon, &tm_year) == 6 && scan_mon(str_mon, &tm_mon)) {
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
  } else if (sscanf(cp, "%d:%d:%d GMT %d %[a-zA-Z] %d", &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon, &tm_year) == 6 && scan_mon(str_mon, &tm_mon)) {
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
  } else if (sscanf(cp, "%[a-zA-Z], %d-%[a-zA-Z]-%d %d:%d:%d GMT", str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, &tm_sec) == 7 && scan_wday(str_wday, &tm_wday) && scan_mon(str_mon, &tm_mon)) {
    tm.tm_wday = tm_wday;
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
  } else if (sscanf(cp, "%[a-zA-Z], %d %[a-zA-Z] %d %d:%d:%d GMT", str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min, &tm_sec) == 7 && scan_wday(str_wday, &tm_wday) && scan_mon(str_mon, &tm_mon)) {
    tm.tm_wday = tm_wday;
    tm.tm_mday = tm_mday;
    tm.tm_mon = tm_mon;
    tm.tm_year = tm_year;
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
  } else if (sscanf(cp, "%[a-zA-Z] %[a-zA-Z] %d %d:%d:%d GMT %d", str_wday, str_mon, &tm_mday, &tm_hour, &tm_min, &tm_sec, &tm_year) == 7 && scan_wday(str_wday, &tm_wday) && scan_mon(str_mon, &tm_mon)) {
    tm.tm_wday = tm_wday;
    tm.tm_mon = tm_mon;
    tm.tm_mday = tm_mday;
    tm.tm_hour = tm_hour;
    tm.tm_min = tm_min;
    tm.tm_sec = tm_sec;
    tm.tm_year = tm_year;
  } else
    return (time_t)-1;
  if (tm.tm_year > 1900)
    tm.tm_year -= 1900;
  else if (tm.tm_year < 70)
    tm.tm_year += 100;
  t = tm_to_time(&tm);
  return t;
}
```