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

```asm
<getRandomHexChars>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x48(%rbp)
  mov    %esi,-0x4c(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x8(%rbp)
  xor    %eax,%eax
  lea    D7(%rip),%rax
  mov    %rax,%rsi
  lea    D5(%rip),%rax
  mov    %rax,%rdi
  call   <fopen@plt>
  mov    %rax,-0x20(%rbp)
  lea    D15(%rip),%rax
  mov    %rax,-0x18(%rbp)
  cmpq   $0x0,-0x20(%rbp)
  je     L38
  mov    -0x20(%rbp),%rdx
  mov    -0x4c(%rbp),%esi
  mov    -0x48(%rbp),%rax
  mov    %rdx,%rcx
  mov    $0x1,%edx
  mov    %rax,%rdi
  call   <fread@plt>
  test   %rax,%rax
  jne    L48
L38:
  mov    -0x48(%rbp),%rax
  mov    %rax,-0x28(%rbp)
  mov    -0x4c(%rbp),%eax
  mov    %eax,-0x2c(%rbp)
  mov    $0x0,%eax
  call   <getpid@plt>
  mov    %eax,-0x34(%rbp)
  lea    -0x10(%rbp),%rax
  mov    $0x0,%esi
  mov    %rax,%rdi
  call   <gettimeofday@plt>
  cmpl   $0x3,-0x2c(%rbp)
  jbe    L2
  lea    -0x10(%rbp),%rax
  lea    0x4(%rax),%rcx
  mov    -0x28(%rbp),%rax
  mov    $0x4,%edx
  mov    %rcx,%rsi
  mov    %rax,%rdi
  call   <memcpy@plt>
  subl   $0x4,-0x2c(%rbp)
  addq   $0x4,-0x28(%rbp)
L2:
  cmpl   $0x3,-0x2c(%rbp)
  jbe    L15
  lea    -0x10(%rbp),%rcx
  mov    -0x28(%rbp),%rax
  mov    $0x4,%edx
  mov    %rcx,%rsi
  mov    %rax,%rdi
  call   <memcpy@plt>
  subl   $0x4,-0x2c(%rbp)
  addq   $0x4,-0x28(%rbp)
L15:
  cmpl   $0x3,-0x2c(%rbp)
  jbe    L75
  lea    -0x34(%rbp),%rcx
  mov    -0x28(%rbp),%rax
  mov    $0x4,%edx
  mov    %rcx,%rsi
  mov    %rax,%rdi
  call   <memcpy@plt>
  subl   $0x4,-0x2c(%rbp)
  addq   $0x4,-0x28(%rbp)
L75:
  movl   $0x0,-0x30(%rbp)
  jmp    L50
L89:
  mov    $0x0,%eax
  call   <rand@plt>
  mov    %eax,%edx
  mov    -0x30(%rbp),%ecx
  mov    -0x48(%rbp),%rax
  add    %rcx,%rax
  movzbl (%rax),%ecx
  mov    -0x30(%rbp),%esi
  mov    -0x48(%rbp),%rax
  add    %rsi,%rax
  xor    %ecx,%edx
  mov    %dl,(%rax)
  addl   $0x1,-0x30(%rbp)
L50:
  mov    -0x30(%rbp),%eax
  cmp    -0x4c(%rbp),%eax
  jb     L89
L48:
  movl   $0x0,-0x30(%rbp)
  jmp    L23
L76:
  mov    -0x30(%rbp),%edx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbq %al,%rax
  and    $0xf,%eax
  mov    %rax,%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  mov    -0x30(%rbp),%ecx
  mov    -0x48(%rbp),%rdx
  add    %rcx,%rdx
  movzbl (%rax),%eax
  mov    %al,(%rdx)
  addl   $0x1,-0x30(%rbp)
L23:
  mov    -0x30(%rbp),%eax
  cmp    -0x4c(%rbp),%eax
  jb     L76
  cmpq   $0x0,-0x20(%rbp)
  je     L0
  mov    -0x20(%rbp),%rax
  mov    %rax,%rdi
  call   <fclose@plt>
L0:
  nop
  mov    -0x8(%rbp),%rax
  sub    %fs:0x28,%rax
  je     L32
  call   <__stack_chk_fail@plt>
L32:
  leave
  ret
```

tool_calls: name: extract_symbolic_data
arguments: data_label: D7
data_type: string
name: extract_symbolic_data
arguments: data_label: D5
data_type: string
name: extract_symbolic_data
arguments: data_label: D15
data_type: string

tool: D7: r

tool: D5: /dev/urandom

tool: D15: 0123456789abcdef

assistant: ```c
void getRandomHexChars(char *p, unsigned int len) {
  FILE *fp = fopen("/dev/urandom", "r");
  char *charset = "0123456789abcdef";
  unsigned int j;
  if (fp == NULL || fread(p, len, 1, fp) == 0) {
    char *x = p;
    unsigned int l = len;
    struct timeval tv;
    pid_t pid = getpid();
    gettimeofday(&tv, NULL);
    if (l >= sizeof(tv.tv_usec)) {
      memcpy(x, &tv.tv_usec, sizeof(tv.tv_usec));
      l -= sizeof(tv.tv_usec);
      x += sizeof(tv.tv_usec);
    }
    if (l >= sizeof(tv.tv_sec)) {
      memcpy(x, &tv.tv_sec, sizeof(tv.tv_sec));
      l -= sizeof(tv.tv_sec);
      x += sizeof(tv.tv_sec);
    }
    if (l >= sizeof(pid)) {
      memcpy(x, &pid, sizeof(pid));
      l -= sizeof(pid);
      x += sizeof(pid);
    }
    for (j = 0; j < len; j++) {
      p[j] ^= rand();
    }
  }
  for (j = 0; j < len; j++) {
    p[j] = charset[p[j] & 0x0F];
  }
  if (fp) {
    fclose(fp);
  }
}
```