Assigning data to 2D array and displaying it C - c

Question

I am writing a program, that will open csv file and save data to 3D array.
Most of code works pretty good, but I have a problem with assiging records to 2D array.
Here is a code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define FILE_MODE "r"
/*
Explode string with given token and assign result to list variable
*/
int explode(const char *src, const char *tokens, char ***list, size_t *len)
{
if(src == NULL || list == NULL || len == NULL) {
return 0;
}
char *str, *copy, **_list = NULL, **tmp;
*list = NULL;
*len = 0;
copy = strdup(src);
if(copy == NULL)
return 1;
str = strtok(copy, tokens);
if(str == NULL) {
goto free_and_exit;
}
_list = realloc(NULL, sizeof *_list);
if(_list == NULL) {
goto free_and_exit;
}
_list[*len] = strdup(str);
if(_list[*len] == NULL)
goto free_and_exit;
(*len)++;
while((str = strtok(NULL, tokens)))
{
tmp = realloc(_list, (sizeof *_list) * (*len + 1));
if(tmp == NULL)
goto free_and_exit;
_list = tmp;
_list[*len] = strdup(str);
if(_list[*len] == NULL)
goto free_and_exit;
(*len)++;
}
free_and_exit:
*list = _list;
free(copy);
return 2;
}
/*
Exploding lines in CSV file
*/
const char* getfield(char* line, int num)
{
const char* tok;
for (tok = strtok(line, ";");
tok && *tok;
tok = strtok(NULL, ";\n"))
{
if (!--num)
return tok;
}
return NULL;
}
int main()
{
FILE *stream;
char fileName[256], table[256], line[256],
**list, **columns, **data;
size_t length;
printf("Witaj uzytkowniku! Podaj nazwe pliku z rozszerzeniem .csv. \n");
scanf("%s", fileName);
explode(fileName, ".", &list, &length);
strcpy(table, list[0]);
stream = fopen("file.csv", FILE_MODE); // not to write path every single time
if (stream == NULL) {
printf("Nie moge otworzyc pliku %s do odczytu!\n", fileName);
exit(1);
}
fgets(line, sizeof line, stream);
explode(line, ";", &columns, &length);
int recordNumber = 0
,columnNumber = 0;
while (fgets(line, sizeof line, stream))
{
char* tmp = strdup(line);
if (getfield(tmp, recordNumber) != NULL) {
columnNumber++;
}
recordNumber++;
free(tmp);
}
fseek(stream, 0, SEEK_SET); // Go to beginning of file
fgets(line, 1024, stream);
int i = 0 // Number of records
,h = 0; // number of columns
char **records[recordNumber][columnNumber];
length = 0;
char *tmp[recordNumber];
// Here I get number of lines and columns in csv file to make 3D array??
while (fgets(line, sizeof line, stream) && i < recordNumber)
{
tmp[i] = strdup(line);
explode(tmp[i], ";", &data, &length);
for (h = 0; h < columnNumber; h++)
{
memcpy(records[i][h], data[h], sizeof(data[h]));
}
i++;
}
for (i = 0; i < recordNumber; i++)
{
for (h = 0; h < columnNumber; h++)
{
printf("%s ", records[i][h][0]);
}
printf("\n");
}
fclose(stream);
return EXIT_SUCCESS;
}
Problem starts, when I try do a loop, that assign data to array:
while (fgets(line, sizeof line, stream) && i < recordNumber)
{
tmp[i] = strdup(line);
explode(tmp[i], ";", &data, &length);
for (h = 0; h < columnNumber; h++)
{
memcpy(records[i][h], data[h], sizeof(data[h]));
}
i++;
}
I tried to use memcpy and strcpy, but none works correctly - I am pretty sure.
When code goes to these lines, there is an error: segmentation fault (core dumping).
All i want to achieve is to fill this array with data from csv file and print it.
Thanks for your help! :)
EDIT:
explode function is not mine. Probably, I found it somewhere on stackoverflow.
When, it comes to the code, after little change, it works
char records[recordNumber][columnNumber][1024];
length = 0;
char *tmp[recordNumber];
while (fgets(line, sizeof line, stream) && i < recordNumber)
{
tmp[i] = strdup(line);
explode(tmp[i], ";", &data, &length);
for (h = 0; h < columnNumber; h++)
{
strcpy(records[i][h], data[h]);
}
i++;
}

Answer 1

Read each line of the file with fgets. strpbrk can be used to find the delimiters. Two pointers can be used to get the number of characters between the delimiters. Then allocate memory and use memcpy to copy the field to the allocated memory.
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
char ***strpdlm ( char *pdelim, int skip);
char ***freedlm ( char ***ppp);
int main()
{
char ***expld = NULL;
int line = 0;
int field = 0;
//last argument of 1 is skip consecutive delimiters. 0 do not skip
expld = strpdlm ( ";\n", 1);// delimiters semicolon and newline
//print each extracted string
line = 0;
if ( expld) {//not null
while ( expld[line]) {//not null
field = 0;
printf ( "\nfields for line %d\n", line);
while ( expld[line][field]) {//not null
printf ( "expld[%d][%d] %s\n", line, field, expld[line][field]);
field++;
}
line++;
}
}
//free memory and set NULL
expld = freedlm ( expld);
return 0;
}
char ***freedlm ( char ***ppp) {
size_t each = 0;
size_t item = 0;
if ( ppp) {
while ( ppp[each]) {
item = 0;
while ( ppp[each][item]) {
free ( ppp[each][item]);
item++;
}
free ( ppp[each]);
each++;
}
free ( ppp);
}
return NULL;
}
char ***strpdlm ( char *pdelim, int skip) {
char ***xpld = NULL;
char ***temprecord = NULL;
char **tempfield = NULL;
char *pnt = NULL;
char *cur = NULL;
char line[1024] = "";
int span = 0;
int len = 0;
int record = 0;
int field = 0;
FILE *pf = NULL;
if ( ( pf = fopen ( "file.csv", "r")) == NULL) {
perror ( "could not open \"file.csv\"");
return NULL;
}
if ( pdelim) {
while ( fgets ( line, sizeof line, pf)) {
//make sure each line ends with \n
len = strcspn ( line, "\n");
if ( len + 1 < sizeof line) {
line[len] = '\n';
line[len + 1] = '\0';
}
//allocate record + 2 pointers
if ( ( temprecord = realloc ( xpld, ( record + 2) * sizeof ( *xpld))) == NULL) {
fprintf ( stderr, "problem realloc records\n");
fclose ( pf);
return xpld;
}
xpld = temprecord;
xpld[record] = NULL;
field = 0;
cur = line;//cur points to line
while ( ( pnt = strpbrk ( cur, pdelim))) {
if ( pnt != cur || !skip) {
if ( ( tempfield = realloc ( xpld[record], ( field + 2) * sizeof ( **xpld))) == NULL) {
fprintf ( stderr, "problem realloc fields\n");
fclose ( pf);
return xpld;
}
xpld[record] = tempfield;
xpld[record][field] = NULL;
if ( pnt) {
span = pnt - cur;
}
else {
span = strlen ( cur);
}
if ( ( xpld[record][field] = malloc ( span + 1)) == NULL) {
fprintf ( stderr, "problem malloc\n");
fclose ( pf);
return xpld;
}
memcpy ( xpld[record][field], cur, span);
xpld[record][field][span] = '\0';
field++;
xpld[record][field] = NULL;//sentinel NULL
}
cur = pnt + 1;//set cur to point to next field
}
record++;
xpld[record] = NULL;//sentinel NULL
}
}
fclose ( pf);
return xpld;
}