Browse Source

string: split strcat and strncat (DONE)

master
Lephenixnoir 8 months ago
parent
commit
3792bbd9d1
Signed by: Lephenixnoir GPG Key ID: 1BBA026E13FC0495
  1. 1
      CMakeLists.txt
  2. 33
      src/libc/string/strcat.c
  3. 12
      src/libc/string/strncat.c

1
CMakeLists.txt

@ -142,6 +142,7 @@ set(SOURCES
src/libc/string/strcpy.c
src/libc/string/strdup.c
src/libc/string/strlen.c
src/libc/string/strncat.c
src/libc/string/strncmp.c
src/libc/string/strncpy.c
src/libc/string/strnlen.c

33
src/libc/string/strcat.c

@ -1,16 +1,5 @@
#include <string.h>
/*
** The strcat() function appends the src string to the dest string,
** overwriting the terminating null byte ('\0') at the end of dest, and then
** adds a terminating null byte. The strings may not overlap, and the dest
** string must have enough space for the result. If dest is not large enough,
** program behavior is unpredictable; buffer overruns are a favorite avenue for
** attacking secure programs.
**
** TODO: use the DMA !
** TODO: look at the DSP ?
*/
char *strcat(char *dest, char const *src)
{
size_t i;
@ -26,25 +15,3 @@ char *strcat(char *dest, char const *src)
dest[i + start] = '\0';
return (dest);
}
/*
** The strncat() function is similar, except that:
** * it will use at most n bytes from src; and
** * src does not need to be null-terminated if it contains n or more bytes.
**
** As with strcat(), the resulting string in dest is always null-terminated.
**
** If src contains n or more bytes, strncat() writes n+1 bytes to dest (n from
** src plus the terminating null byte). Therefore, the size of dest must be at
** least strlen(dest)+n+1.
*/
char *strncat(char *dest, const char *src, size_t n)
{
size_t dest_len = strlen(dest);
size_t i;
for (i = 0; i < n && src[i] != '\0'; i++)
dest[dest_len + i] = src[i];
dest[dest_len + i] = '\0';
return (dest);
}

12
src/libc/string/strncat.c

@ -0,0 +1,12 @@
#include <string.h>
char *strncat(char *dest, const char *src, size_t n)
{
size_t dest_len = strlen(dest);
size_t i;
for (i = 0; i < n && src[i] != '\0'; i++)
dest[dest_len + i] = src[i];
dest[dest_len + i] = '\0';
return (dest);
}
Loading…
Cancel
Save