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fix(bin.c): safer generate_id()

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set next byte of ID to zero each time a new character is appended to
prevent undefined behaviours.
This commit is contained in:
Tom MTT. 2022-11-21 19:31:20 +01:00
parent fdf588e523
commit de51c9830a
1 changed files with 2 additions and 3 deletions
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5
bin.c
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@ -34,7 +34,7 @@ char *generate_id(int min_length)
/* allocate a buffer to store the ID */ /* allocate a buffer to store the ID */
char *buffer; char *buffer;
if ((buffer = calloc(length + 1, sizeof(char))) == NULL) if ((buffer = malloc((length + 1) * sizeof(char))) == NULL)
return NULL; return NULL;
/* for each letter, generate a random one */ /* for each letter, generate a random one */
@ -43,6 +43,7 @@ char *generate_id(int min_length)
return NULL; return NULL;
buffer[i] = id_symbols[rand() % strlen(id_symbols)]; buffer[i] = id_symbols[rand() % strlen(id_symbols)];
buffer[i + 1] = 0;
/* collision? */ /* collision? */
if (i == length - 1 && paste_exists(buffer)) { if (i == length - 1 && paste_exists(buffer)) {
@ -54,12 +55,10 @@ char *generate_id(int min_length)
free(buffer); free(buffer);
return NULL; return NULL;
} }
buffer = tmp; buffer = tmp;
} }
} }
buffer[length] = 0;
return buffer; return buffer;
} }