Nested strtok_r : command line argument parsing - c

Question

CODE HERE: http://ideone.com/AZnXFm
#include <stdio.h>
#include <stdlib.h>
#include<string.h>
int main()
{
char *buffer;
size_t bufsize = 32;
size_t characters;
buffer = (char *)malloc(bufsize * sizeof(char));
if( buffer == NULL)
{
perror("Unable to allocate buffer");
exit(1);
}
printf("Type something: ");
characters = getline(&buffer,&bufsize,stdin);
printf("%zu characters were read.\n",characters);
printf("You typed: %s",buffer);
char *end_str,*token2;
char *token = strtok_r(buffer,";",&end_str);
printf("token : %s \n", token);
int count =0,wordcnt=0;
while(token !=NULL)
{
char *end_token;
count++;
printf("outside count ------------------------%d\n", count);
strtok_r(token," ",&end_token);
while(token2!=NULL)
{
wordcnt++;
printf("insdie count %d\n",wordcnt);
printf("%s------------------- \n", token2);
token2 = strtok_r(NULL," ",&end_token);
}
token = strtok_r(NULL, ";",&end_str);
}
return(0);
}
Output is
Type something: rosie is; really good
22 characters were read.
You typed: rosie is; really good
token : rosie is
outside count ------------------------1
insdie count 1
AWAVA��AUATL�% -------------------
insdie count 2
is-------------------
outside count ------------------------2

Answer 1

A number of basic fixes are needed or have been applied in the code below:
Let getline() do the memory allocation.
Check that getline() read a line.
Free the memory allocated.
Set token2 with inner strtok_r() call.
Make variable names a bit more systematic.
Make characters into ssize_t to match the return from getline().
Print characters using %zd. This is marginally controversial; it prints the signed variant of size_t with the z-qualified signed decimal format string. It makes sense (to me at least and my compiler — GCC 6.2.0 on macOS Sierra), but I'm not sure where to find the confirmation that it is officially sanctioned by (the POSIX) standards.
Renaming variables for consistency.
Other minor cosmetic fixups (the print formatting could still be improved — quite a lot).
Leading to:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void)
{
char *buffer = 0;
size_t bufsize = 0;
ssize_t characters;
printf("Type something: ");
characters = getline(&buffer, &bufsize, stdin);
printf("%zd characters were read.\n", characters);
if (characters > 0)
{
printf("You typed: %s", buffer);
char *end_str1;
char *token1 = strtok_r(buffer, ";", &end_str1);
printf("token: %s \n", token1);
int count = 0, wordcnt = 0;
while (token1 != NULL)
{
char *end_str2;
count++;
printf("outside count ------------------------%d\n", count);
char *token2 = strtok_r(token1, " ", &end_str2);
while (token2 != NULL)
{
wordcnt++;
printf("inside count %d\n", wordcnt);
printf("%s------------------- \n", token2);
token2 = strtok_r(NULL, " ", &end_str2);
}
token1 = strtok_r(NULL, ";", &end_str1);
}
}
free(buffer);
return(0);
}
Example run:
Type something: rosie is; really good
22 characters were read.
You typed: rosie is; really good
token: rosie is
outside count ------------------------1
inside count 1
rosie-------------------
inside count 2
is-------------------
outside count ------------------------2
inside count 3
really-------------------
inside count 4
good
-------------------