can sprintf be used to initialize values

[ebon shore]

void initAnimal(int i, SpeciesType s, char *n, char *g, int a, AnimalType *an)
{
  an->species = s;
  an->age = a;
  sprintf(an->gender, "%31s", g);
  sprintf(an->name, "%31s", n);
  an->id = i;
}
```like is the above correct

[vernal burrow]

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[coarse torrent]

assuming those fields are arrays, that would work

though this function seems pretty unnecessary

looks like it will add a bunch of spaces to the end of the string if it is too short too

very strange

[ebon shore]

what fields are you referring to? the AnimalType *an or all?

[coarse torrent]

the gender and name fields

[delicate oak]

use snprintf and %s

actually, just use memcpy since you're not formatting anything

void initAnimal(int i, SpeciesType s, const char *n, const char *g, int a, AnimalType *an)
{
  an->species = s;
  an->age = a;
  const n_len = strlen(n);
  const g_len = strlen(g);
  /* too long */
  if(g_len < 32)
    memcpy(an->gender, g, g_len + 1);
  else
    memcpy(an->gender, "TOO LONG", 9);

  if(n_len < 32)
    memcpy(an->name, n, n_len + 1);
  else
    memcpy(an->name, "TOO LONG", 9);
  an->id = i;
}

@ebon shore your current code breaks if you supply a larger string btw

;compile -fsanitize=address

#include <string.h>
#include <stdio.h>
typedef int SpeciesType;
typedef struct {
  SpeciesType species;
  int         age;
  int         id;
  char        gender[32];
  char        name[32];
} AnimalType;

void initAnimal(int i, SpeciesType s, char *n, char *g, int a, AnimalType *an)
{
  an->species = s;
  an->age = a;
  sprintf(an->gender, "%31s", g);
  sprintf(an->name, "%31s", n);
  an->id = i;
}

int main(void) {
    AnimalType a;
    initAnimal(1337, 0xbeef, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", 20, &a);
}

[gloomy widget]

Compiler Output

=================================================================
==1==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fff1a89938c at pc 0x7f0464235bbd bp 0x7fff1a8991d0 sp 0x7fff1a898980
WRITE of size 111 at 0x7fff1a89938c thread T0
    #0 0x7f0464235bbc in vsprintf (/opt/compiler-explorer/gcc-12.2.0/lib64/libasan.so.8+0x76bbc)
    #1 0x7f0464235dbe in __interceptor_sprintf (/opt/compiler-explorer/gcc-12.2.0/lib64/libasan.so.8+0x76dbe)
    #2 0x401249 in initAnimal /app/example.c:16
    #3 0x401362 in main /app/example.c:23
    #4 0x7f0463ff1082 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x24082)
    #5 0x4010cd in _start (/app/output.s+0x4010cd)

Address 0x7fff1a89938c is located in stack of thread T0 at offset 124 in frame
    #0 0x4012c2 in main /app/example.c:21

  This frame has 1 object(s):
    [48, 124) 'a' (line 22) <== Memory access at offset 124 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind

cancername#4387 | 92ms | c | x86-64 gcc 12.2 | godbolt.org

[vernal burrow]

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[ebon shore]

a bit late but thank you both for the reply!!

!solved