YAIP/src/util.c

#include "util.h"

int strpos(char *haystack, char *needle) {
	char *p = strstr(haystack, needle);
	if ( p != NULL ) return p - haystack;
	return -1;
}

int countLines(char fileName[]){
	FILE *fp;
	char ch;
	int linesCount = 0;
	fp=fopen(fileName,"r");
	if(fp==NULL) {
		printf("File \"%s\" does not exist!!!\n",fileName);
		return -1;
	}
	//read character by character and check for new line
	while((ch=fgetc(fp))!=EOF) {
		if(ch=='\n')
		linesCount++;
	}
	//close the file
	fclose(fp);
	return linesCount;
}

/* Read characters from 'fd' until a newline is encountered. If a newline
  character is not encountered in the first (n - 1) bytes, then the excess
  characters are discarded. The returned string placed in 'buf' is
  null-terminated and includes the newline character if it was read in the
  first (n - 1) bytes. The function return value is the number of bytes
  placed in buffer (which includes the newline character if encountered,
  but excludes the terminating null byte). */
ssize_t fdReadLine(int fd, void *buffer, size_t n) {
	ssize_t numRead;                    /* # of bytes fetched by last read() */
	size_t totRead;                     /* Total bytes read so far */
	char *buf;
	char ch;
	if (n <= 0 || buffer == NULL) {
		errno = EINVAL;
		return -1;
	}
	buf = buffer;                       /* No pointer arithmetic on "void *" */
	totRead = 0;
	for (;;) {
		numRead = read(fd, &ch, 1);
		if (numRead == -1) {
			if (errno == EINTR)         /* Interrupted --> restart read() */
			continue;
			else
			return -1;              /* Some other error */

		} else if (numRead == 0) {      /* EOF */
			if (totRead == 0)           /* No bytes read; return 0 */
			return 0;
			else                        /* Some bytes read; add '\0' */
			break;

		} else {                        /* 'numRead' must be 1 if we get here */
			if (totRead < n - 1) {      /* Discard > (n - 1) bytes */
				totRead++;
				*buf++ = ch;
			}

			if (ch == '\n')
			break;
		}
	}

	*buf = '\0';
	return totRead;
}