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

```asm
<main>:
  endbr64
  push   %r13
  push   %r12
  push   %rbp
  lea    D39(%rip),%rbp
  push   %rbx
  mov    %rbp,%rsi
  sub    $0x58,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x48(%rsp)
  xor    %eax,%eax
  mov    %rsp,%rbx
  mov    %rbx,%rdi
  call   <mystrcpy@plt>
  movabs $0x6f77206f6c6c6548,%rax
  cmp    %rax,(%rsp)
  je     L76
L66:
  mov    $0x1,%edi
L61:
  xor    $0x1,%edi
  lea    D73(%rip),%r13
  call   <assert@plt>
  lea    D121(%rip),%rsi
  mov    %rbx,%rdi
  call   <strcmp@plt>
  mov    %eax,%edi
  call   <assert@plt>
  lea    D94(%rip),%rsi
  mov    %rbx,%rdi
  call   <strcmp@plt>
  mov    %eax,%edi
  call   <assert@plt>
  mov    %r13,%rsi
  mov    %rbx,%rdi
  call   <mystrcpy@plt>
  mov    %r13,%rsi
  mov    %rbx,%rdi
  call   <mystrcpy@plt>
  xor    %edi,%edi
  cmpb   $0x0,(%rax)
  sete   %dil
  call   <assert@plt>
  mov    %rbp,%rdi
  call   <mystrlen@plt>
  xor    %edi,%edi
  cmp    $0xb,%eax
  sete   %dil
  call   <assert@plt>
  mov    %rbp,%rdi
  call   <mystrlen@plt>
  xor    %edi,%edi
  cmp    $0xb,%eax
  sete   %dil
  call   <assert@plt>
  mov    %rbp,%rdi
  call   <mystrlen@plt>
  xor    %edi,%edi
  cmp    $0xb,%eax
  sete   %dil
  call   <assert@plt>
  mov    %rbp,%rdi
  call   <mystrlen@plt>
  xor    %edi,%edi
  cmp    $0xb,%eax
  sete   %dil
  call   <assert@plt>
  mov    %rbp,%rdi
  call   <mystrdup@plt>
  mov    %rbp,%rsi
  mov    %rax,%rdi
  mov    %rax,%r12
  call   <strcmp@plt>
  xor    %edi,%edi
  test   %eax,%eax
  sete   %dil
  call   <assert@plt>
  movb   $0x59,(%r12)
  lea    D2(%rip),%rsi
  mov    %r12,%rdi
  call   <strcmp@plt>
  xor    %edi,%edi
  test   %eax,%eax
  sete   %dil
  call   <assert@plt>
  mov    %r12,%rdi
  call   <free@plt>
  lea    D37(%rip),%rsi
  mov    %rbx,%rdi
  call   <mystrcpy@plt>
  lea    D147(%rip),%rsi
  mov    %rbx,%rdi
  call   <mystrcat@plt>
  movabs $0x746973726576696e,%rax
  xor    0x8(%rsp),%rax
  movabs $0x5520657564727550,%rdx
  xor    (%rsp),%rdx
  or     %rdx,%rax
  jne    L73
  xor    %edi,%edi
  cmpw   $0x79,0x10(%rsp)
  je     L32
L73:
  mov    $0x1,%edi
L32:
  xor    $0x1,%edi
  call   <assert@plt>
  mov    %r13,%rsi
  mov    %rbx,%rdi
  call   <mystrcat@plt>
  movabs $0x746973726576696e,%rax
  xor    0x8(%rsp),%rax
  movabs $0x5520657564727550,%rdx
  xor    (%rsp),%rdx
  or     %rdx,%rax
  jne    L17
  xor    %edi,%edi
  cmpw   $0x79,0x10(%rsp)
  je     L58
L17:
  mov    $0x1,%edi
L58:
  xor    $0x1,%edi
  lea    D77(%rip),%rbp
  call   <assert@plt>
  lea    D12(%rip),%rsi
  mov    %rbx,%rdi
  call   <mystrcpy@plt>
  mov    %rbp,%rsi
  mov    %rbx,%rdi
  call   <mystrstr@plt>
  lea    D141(%rip),%rsi
  mov    %rax,%rdi
  call   <strcmp@plt>
  xor    %edi,%edi
  test   %eax,%eax
  sete   %dil
  call   <assert@plt>
  lea    D18(%rip),%rsi
  mov    %rbx,%rdi
  call   <mystrstr@plt>
  xor    %edi,%edi
  test   %rax,%rax
  sete   %dil
  call   <assert@plt>
  mov    %rbx,%rsi
  mov    %rbp,%rdi
  lea    D118(%rip),%rbp
  call   <mystrstr@plt>
  xor    %edi,%edi
  test   %rax,%rax
  sete   %dil
  call   <assert@plt>
  mov    %r13,%rsi
  mov    %rbx,%rdi
  call   <mystrstr@plt>
  xor    %edi,%edi
  cmp    %rax,%rbx
  sete   %dil
  call   <assert@plt>
  lea    D110(%rip),%rsi
  mov    %rbp,%rdi
  call   <mystrcmp@plt>
  shr    $0x3f,%rax
  mov    %rax,%rdi
  call   <assert@plt>
  mov    %rbp,%rsi
  lea    D114(%rip),%rbp
  mov    %rbp,%rdi
  call   <mystrcmp@plt>
  xor    %edi,%edi
  test   %rax,%rax
  setg   %dil
  call   <assert@plt>
  mov    %rbp,%rsi
  mov    %rbp,%rdi
  call   <mystrcmp@plt>
  xor    %edi,%edi
  test   %rax,%rax
  sete   %dil
  call   <assert@plt>
  lea    D7(%rip),%rdi
  call   <printf@plt>
  mov    0x48(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L42
  add    $0x58,%rsp
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  ret
L76:
  xor    %edi,%edi
  cmpl   $0x646c72,0x8(%rsp)
  jne    L66
  jmp    L61
L42:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: read_data
arguments: data_label: D39
type_infered: string
name: read_data
arguments: data_label: D73
type_infered: string
name: read_data
arguments: data_label: D121
type_infered: string
name: read_data
arguments: data_label: D94
type_infered: string
name: read_data
arguments: data_label: D2
type_infered: string
name: read_data
arguments: data_label: D37
type_infered: string
name: read_data
arguments: data_label: D147
type_infered: string
name: read_data
arguments: data_label: D77
type_infered: string
name: read_data
arguments: data_label: D12
type_infered: string
name: read_data
arguments: data_label: D141
type_infered: string
name: read_data
arguments: data_label: D18
type_infered: string
name: read_data
arguments: data_label: D118
type_infered: string
name: read_data
arguments: data_label: D110
type_infered: string
name: read_data
arguments: data_label: D114
type_infered: string
name: read_data
arguments: data_label: D7
type_infered: string

tool: D39: Hello world

tool: 

tool: D121: Hello worl

tool: D94: Hello worldgggg

tool: D2: Yello world

tool: D37: Purdue

tool: D147:  University

tool: D77: jumps

tool: D12: The quick brown fox jumps over the lazy dog

tool: D141: jumps over the lazy dog

tool: D18: Hello

tool: D118: abcd

tool: D110: dabc

tool: D114: dab

tool: D7: Seems to be OK


assistant: ```c
int main() {
  char s1[64], *s2;
  mystrcpy(s1, "Hello world");
  assert(!strcmp(s1, "Hello world"));
  assert(strcmp(s1, "Hello worl"));
  assert(strcmp(s1, "Hello worldgggg"));
  mystrcpy(s1, "");
  assert(!strcmp(mystrcpy(s1, ""), ""));
  assert(mystrlen("Hello world") == 11);
  assert(mystrlen("Hello world") == 11);
  assert(mystrlen("Hello world") == 11);
  assert(mystrlen("Hello world") == 11);
  s2 = mystrdup("Hello world");
  assert(!strcmp(s2, "Hello world"));
  s2[0] = 'Y';
  assert(!strcmp(s2, "Yello world"));
  free(s2);
  mystrcpy(s1, "Purdue");
  mystrcat(s1, " University");
  assert(!strcmp(s1, "Purdue University"));
  mystrcat(s1, "");
  assert(!strcmp(s1, "Purdue University"));
  mystrcpy(s1, "The quick brown fox jumps over the lazy dog");
  s2 = mystrstr(s1, "jumps");
  assert(!strcmp(s2, "jumps over the lazy dog"));
  assert(mystrstr(s1, "Hello") == NULL);
  assert(mystrstr("jumps", s1) == NULL);
  s2 = mystrstr(s1, "");
  assert(s2 == s1);
  assert(mystrcmp("abcd", "dabc") < 0);
  assert(mystrcmp("dab", "abcd") > 0);
  assert(mystrcmp("dab", "dab") == 0);
  printf("Seems to be OK\n");
  return 0;
}
```