user: Please show me the C implementation that matches the assembly code listed below:

```asm
<echo>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %rbx
  lea    -0x100000(%rsp),%r11
L84:
  sub    $0x1000,%rsp
  orq    $0x0,(%rsp)
  cmp    %r11,%rsp
  jne    L84
  sub    $0x88,%rsp
  mov    %edi,-0x100084(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x18(%rbp)
  xor    %eax,%eax
  movl   $0x8,-0x10007c(%rbp)
L65:
  lea    -0x10007c(%rbp),%rcx
  lea    -0x100054(%rbp),%rdx
  lea    -0x100020(%rbp),%rsi
  mov    -0x100084(%rbp),%eax
  mov    %rcx,%r9
  mov    %rdx,%r8
  mov    $0x0,%ecx
  mov    $0x100000,%edx
  mov    %eax,%edi
  call   <recvfrom@plt>
  mov    %eax,-0x100058(%rbp)
  mov    -0x100054(%rbp),%eax
  mov    %eax,%edi
  call   <ntohs@plt>
  mov    %eax,%ebx
  mov    -0x100050(%rbp),%eax
  mov    %eax,%edi
  call   <inet_ntoa@plt>
  mov    %ebx,%edx
  mov    %rax,%rsi
  lea    D219(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  cmpl   $0x0,-0x100058(%rbp)
  jns    L41
  lea    D84(%rip),%rax
  mov    %rax,%rdi
  call   <perror@plt>
  jmp    L65
L41:
  mov    -0x100058(%rbp),%eax
  mov    %eax,%esi
  lea    D144(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  lea    -0x100040(%rbp),%rax
  lea    D62(%rip),%rdx
  mov    %rdx,%rsi
  mov    %rax,%rdi
  call   <strcpy@plt>
  lea    -0x100040(%rbp),%rcx
  lea    -0x10007d(%rbp),%rdx
  lea    -0x100020(%rbp),%rax
  lea    D24(%rip),%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sscanf@plt>
  movzbl -0x10007d(%rbp),%eax
  movsbl %al,%eax
  lea    -0x100040(%rbp),%rdx
  mov    %eax,%esi
  lea    D69(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  movzbl -0x10007d(%rbp),%eax
  cmp    $0x58,%al
  jne    L68
  lea    -0x100064(%rbp),%r8
  lea    -0x10006c(%rbp),%rdi
  lea    -0x100070(%rbp),%rcx
  lea    -0x100074(%rbp),%rdx
  lea    -0x100040(%rbp),%rax
  lea    -0x10005c(%rbp),%rsi
  push   %rsi
  lea    -0x100060(%rbp),%rsi
  push   %rsi
  mov    %r8,%r9
  mov    %rdi,%r8
  lea    D148(%rip),%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sscanf@plt>
  add    $0x10,%rsp
  mov    -0x100064(%rbp),%edx
  mov    -0x100074(%rbp),%eax
  mov    %eax,%esi
  lea    D202(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100060(%rbp),%edx
  mov    -0x100070(%rbp),%eax
  mov    %eax,%esi
  lea    D231(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x10005c(%rbp),%edx
  mov    -0x10006c(%rbp),%eax
  mov    %eax,%esi
  lea    D5(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100064(%rbp),%edx
  mov    -0x100074(%rbp),%eax
  mov    %edx,%esi
  mov    %eax,%edi
  call   <led@plt>
  mov    -0x100060(%rbp),%edx
  mov    -0x100070(%rbp),%eax
  mov    %edx,%esi
  mov    %eax,%edi
  call   <led@plt>
  mov    -0x10005c(%rbp),%edx
  mov    -0x10006c(%rbp),%eax
  mov    %edx,%esi
  mov    %eax,%edi
  call   <led@plt>
  jmp    L65
L68:
  movzbl -0x10007d(%rbp),%eax
  cmp    $0x53,%al
  jne    L71
  lea    -0x100068(%rbp),%rcx
  lea    -0x100078(%rbp),%rdx
  lea    -0x100040(%rbp),%rax
  lea    D127(%rip),%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sscanf@plt>
  mov    -0x100068(%rbp),%edx
  mov    -0x100078(%rbp),%eax
  mov    %eax,%esi
  lea    D236(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100068(%rbp),%edx
  mov    -0x100078(%rbp),%eax
  mov    %edx,%esi
  mov    %eax,%edi
  call   <led@plt>
  jmp    L65
L71:
  movzbl -0x10007d(%rbp),%eax
  cmp    $0x52,%al
  jne    L43
  lea    -0x100078(%rbp),%rdx
  lea    -0x100040(%rbp),%rax
  lea    D74(%rip),%rcx
  mov    %rcx,%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sscanf@plt>
  mov    -0x100078(%rbp),%eax
  mov    %eax,%esi
  lea    D159(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100078(%rbp),%eax
  mov    %eax,%edi
  call   <get_led_duty@plt>
  mov    %eax,-0x100068(%rbp)
  mov    -0x100068(%rbp),%edx
  lea    -0x10004a(%rbp),%rax
  lea    D75(%rip),%rcx
  mov    %rcx,%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sprintf@plt>
  mov    -0x10007c(%rbp),%ecx
  lea    -0x100054(%rbp),%rdx
  lea    -0x10004a(%rbp),%rsi
  mov    -0x100084(%rbp),%eax
  mov    %ecx,%r9d
  mov    %rdx,%r8
  mov    $0x0,%ecx
  mov    $0x4,%edx
  mov    %eax,%edi
  call   <sendto@plt>
  jmp    L65
L43:
  movzbl -0x10007d(%rbp),%eax
  cmp    $0x59,%al
  jne    L65
  lea    -0x10006c(%rbp),%rsi
  lea    -0x100070(%rbp),%rcx
  lea    -0x100074(%rbp),%rdx
  lea    -0x100040(%rbp),%rax
  mov    %rsi,%r8
  lea    D197(%rip),%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sscanf@plt>
  mov    -0x100074(%rbp),%eax
  mov    %eax,%esi
  lea    D153(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100070(%rbp),%eax
  mov    %eax,%esi
  lea    D71(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x10006c(%rbp),%eax
  mov    %eax,%esi
  lea    D170(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100074(%rbp),%eax
  mov    %eax,%edi
  call   <get_led_duty@plt>
  mov    %eax,-0x100064(%rbp)
  mov    -0x100070(%rbp),%eax
  mov    %eax,%edi
  call   <get_led_duty@plt>
  mov    %eax,-0x100060(%rbp)
  mov    -0x10006c(%rbp),%eax
  mov    %eax,%edi
  call   <get_led_duty@plt>
  mov    %eax,-0x10005c(%rbp)
  mov    -0x100064(%rbp),%eax
  mov    %eax,%esi
  lea    D9(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x100060(%rbp),%eax
  mov    %eax,%esi
  lea    D53(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x10005c(%rbp),%eax
  mov    %eax,%esi
  lea    D175(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x10005c(%rbp),%ecx
  mov    -0x100060(%rbp),%edx
  mov    -0x100064(%rbp),%eax
  mov    %eax,%esi
  lea    D28(%rip),%rax
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <printf@plt>
  mov    -0x10005c(%rbp),%esi
  mov    -0x100060(%rbp),%ecx
  mov    -0x100064(%rbp),%edx
  lea    -0x10004a(%rbp),%rax
  mov    %esi,%r8d
  lea    D28(%rip),%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   <sprintf@plt>
  mov    -0x10007c(%rbp),%ecx
  lea    -0x100054(%rbp),%rdx
  lea    -0x10004a(%rbp),%rsi
  mov    -0x100084(%rbp),%eax
  mov    %ecx,%r9d
  mov    %rdx,%r8
  mov    $0x0,%ecx
  mov    $0xa,%edx
  mov    %eax,%edi
  call   <sendto@plt>
  jmp    L65
```

tool_calls: name: retrieve_data
arguments: tag: D219
data_type: string
name: retrieve_data
arguments: tag: D84
data_type: string
name: retrieve_data
arguments: tag: D144
data_type: string
name: retrieve_data
arguments: tag: D62
data_type: string
name: retrieve_data
arguments: tag: D24
data_type: string
name: retrieve_data
arguments: tag: D69
data_type: string
name: retrieve_data
arguments: tag: D148
data_type: string
name: retrieve_data
arguments: tag: D202
data_type: string
name: retrieve_data
arguments: tag: D231
data_type: string
name: retrieve_data
arguments: tag: D5
data_type: string
name: retrieve_data
arguments: tag: D127
data_type: string
name: retrieve_data
arguments: tag: D236
data_type: string
name: retrieve_data
arguments: tag: D74
data_type: string
name: retrieve_data
arguments: tag: D159
data_type: string
name: retrieve_data
arguments: tag: D75
data_type: string
name: retrieve_data
arguments: tag: D197
data_type: string
name: retrieve_data
arguments: tag: D153
data_type: string
name: retrieve_data
arguments: tag: D71
data_type: string
name: retrieve_data
arguments: tag: D170
data_type: string
name: retrieve_data
arguments: tag: D9
data_type: string
name: retrieve_data
arguments: tag: D53
data_type: string
name: retrieve_data
arguments: tag: D175
data_type: string
name: retrieve_data
arguments: tag: D28
data_type: string

tool: D219: Got a datagram from %s port %d


tool: D84: Error receiving data

tool: D144: GOT %d BYTES


tool: 

tool: D24: %c%s

tool: D69: cmd:%c-arg:%s


tool: D148: %3d%3d%3d%3d%3d%3d

tool: D202: rchan: %d rval: %d


tool: D231: gchan: %d gval: %d


tool: D5: bchan: %d bval: %d


tool: D127: %3d%3d

tool: D236: chan: %d val: %d


tool: D74: %3d

tool: D159: read chan: %03d


tool: D75: %03d


tool: D197: %3d%3d%3d

tool: D153: read rchan: %03d


tool: D71: read gchan: %03d


tool: D170: read bchan: %03d


tool: D9: read rval: %03d


tool: D53: read gval: %03d


tool: D175: read bval: %03d


tool: D28: %03d%03d%03d


assistant: ```c
void echo(int sd) {
  int len, n;
  char bufin[1024 * 1024];
  char cmd;
  char arg[20];
  char str_val[10];
  struct sockaddr_in remote;
  int chan, rchan, gchan, bchan;
  int val, rval, gval, bval;
  len = sizeof(remote);
  while (1) {
    n = recvfrom(sd, bufin, 1024 * 1024, 0, (struct sockaddr *)&remote, &len);
    printf("Got a datagram from %s port %d\n", inet_ntoa(remote.sin_addr), ntohs(remote.sin_port));
    if (n < 0) {
      perror("Error receiving data");
    } else {
      printf("GOT %d BYTES\n", n);
      strcpy(arg, "");
      sscanf(bufin, "%c%s", &cmd, &arg);
      printf("cmd:%c-arg:%s\n", cmd, arg);
      if (cmd == 'X') {
        sscanf(arg, "%3d%3d%3d%3d%3d%3d", &rchan, &gchan, &bchan, &rval, &gval, &bval);
        printf("rchan: %d rval: %d\n", rchan, rval);
        printf("gchan: %d gval: %d\n", gchan, gval);
        printf("bchan: %d bval: %d\n", bchan, bval);
        led(rchan, rval);
        led(gchan, gval);
        led(bchan, bval);
      } else if (cmd == 'S') {
        sscanf(arg, "%3d%3d", &chan, &val);
        printf("chan: %d val: %d\n", chan, val);
        led(chan, val);
      } else if (cmd == 'R') {
        sscanf(arg, "%3d", &chan);
        printf("read chan: %03d\n", chan);
        val = get_led_duty(chan);
        sprintf(str_val, "%03d\n", val);
        sendto(sd, str_val, 4, 0, (struct sockaddr *)&remote, len);
      } else if (cmd == 'Y') {
        sscanf(arg, "%3d%3d%3d", &rchan, &gchan, &bchan);
        printf("read rchan: %03d\n", rchan);
        printf("read gchan: %03d\n", gchan);
        printf("read bchan: %03d\n", bchan);
        rval = get_led_duty(rchan);
        gval = get_led_duty(gchan);
        bval = get_led_duty(bchan);
        printf("read rval: %03d\n", rval);
        printf("read gval: %03d\n", gval);
        printf("read bval: %03d\n", bval);
        printf("%03d%03d%03d\n", rval, gval, bval);
        sprintf(str_val, "%03d%03d%03d\n", rval, gval, bval);
        sendto(sd, str_val, 10, 0, (struct sockaddr *)&remote, len);
      }
    }
  }
}
```