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

```asm
<string_join>:
  endbr64
  push   %r15
  lea    -0x1(%rsi),%rax
  push   %r14
  mov    %rdx,%r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %r8,(%rsp)
  mov    %rax,0x18(%rsp)
  test   %rsi,%rsi
  je     L64
  mov    %rdi,%r15
  mov    %rsi,%r13
  mov    %rcx,%r12
  xor    %ebx,%ebx
  xor    %ebp,%ebp
  nopl   0x0(%rax,%rax,1)
L56:
  mov    (%r15,%rbx,8),%rdi
  call   <string_len@plt>
  mov    %rbx,0x10(%rsp)
  lea    0x1(%rbx),%rbx
  cltq
  add    %rax,%rbp
  cmp    %rbx,%r13
  jne    L56
  mov    %r14,%rdi
  call   <string_len@plt>
  xor    %edi,%edi
  cltq
  imul   0x18(%rsp),%rax
  lea    0x1(%rbp,%rax,1),%rax
  cmp    %rax,(%rsp)
  setae  %dil
  xor    %ebp,%ebp
  call   <assert@plt>
  mov    (%r15),%rdi
  movq   $0x0,0x8(%rsp)
  call   <string_len@plt>
  movslq %eax,%r8
  test   %r8,%r8
  je     L101
  nopl   0x0(%rax,%rax,1)
L3:
  movslq %ebp,%rdi
  xor    %edx,%edx
  add    %r12,%rdi
  nopl   0x0(%rax,%rax,1)
L93:
  mov    (%r15),%rcx
  movzbl (%rcx,%rdx,1),%ecx
  mov    %cl,(%rdi,%rdx,1)
  add    $0x1,%rdx
  cmp    %r8,%rdx
  jne    L93
  mov    0x18(%rsp),%rsi
  lea    0x0(%rbp,%rax,1),%ebx
  cmp    %rsi,0x8(%rsp)
  jb     L10
L14:
  movslq %ebx,%rax
  mov    %ebx,%ebp
  movb   $0x0,(%r12,%rax,1)
L92:
  mov    0x8(%rsp),%rsi
  add    $0x8,%r15
  lea    0x1(%rsi),%rax
  cmp    0x10(%rsp),%rsi
  je     L76
  mov    (%r15),%rdi
  mov    %rax,0x8(%rsp)
  call   <string_len@plt>
  movslq %eax,%r8
  test   %r8,%r8
  jne    L3
L101:
  mov    0x18(%rsp),%rsi
  mov    %ebp,%ebx
  cmp    %rsi,0x8(%rsp)
  jae    L14
  nopl   0x0(%rax)
L10:
  movslq %ebx,%rax
  xor    %r13d,%r13d
  mov    %rax,(%rsp)
  jmp    L11
  nopl   0x0(%rax)
L51:
  mov    (%rsp),%rax
  movzbl (%r14,%r13,1),%ecx
  add    %r12,%rax
  mov    %cl,(%rax,%r13,1)
  add    $0x1,%r13
L11:
  mov    %r14,%rdi
  lea    (%rbx,%r13,1),%ebp
  call   <string_len@plt>
  cmp    %r13d,%eax
  jg     L51
  jmp    L92
  nop
L76:
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L64:
  mov    %rdx,%rdi
  call   <string_len@plt>
  xor    %edi,%edi
  movslq %eax,%rdx
  mov    $0x1,%eax
  sub    %rdx,%rax
  cmp    %rax,(%rsp)
  setae  %dil
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  jmp    1060 <assert@plt>
```

assistant: ```c
void string_join(char *stringArray[], size_t capacity, char *separator, char *res, size_t maxRes) {
  int i, k, l, pos = 0;
  size_t currentStrLength, totalCharLength = 0;
  for (i = 0; i < capacity; i++) {
    totalCharLength = totalCharLength + string_len(stringArray[i]);
  }
  totalCharLength = totalCharLength + ((capacity - 1) * string_len(separator)) + 1;
  assert(maxRes >= totalCharLength);
  for (i = 0; i < capacity; i++) {
    currentStrLength = string_len(stringArray[i]);
    for (k = 0; k < currentStrLength; k++) {
      res[pos] = stringArray[i][k];
      pos++;
    }
    if (i < capacity - 1) {
      for (l = 0; l < string_len(separator); l++) {
        res[pos] = separator[l];
        pos++;
      }
    } else {
      res[pos] = '\0';
    }
  }
}
```