Implement grid resizing.

src/csv-data-manipulation.c

@@ -8,6 +8,7 @@
 #include <stdlib.h> /* malloc...*/
 #include <string.h> /* strtok...*/
 #include <ctype.h>
+#include <errno.h>
 
 
 /**
@@ -65,52 +66,78 @@ int csv_destroy(CSV * csv) {
 }
 
 
+/**
+ * Get value in CSV table at COL, ROW
+ */
+char * csv_get(CSV * csv, unsigned int col, unsigned int row) {
+	return NULL;
+}
+
+
+/**
+ * Set value in CSV table at COL, ROW
+ */
+int csv_set(CSV * csv, unsigned int col, unsigned int row, char * value) {
+	return 0;
+}
+
 /* Resize CSV table
  * - grow columns: on each row, add missing columns cells 
  * - grow rows: add now rows, with all columns count
  * - reduce columns: remove columns from right 
  * - reduce lines: remove columns from the end
  */
-int csv_resize(CSV * csv, unsigned int new_cols, unsigned int new_rows) {
-	char ** new_table;
+int csv_resize(CSV * old_csv, unsigned int new_cols, unsigned int new_rows) {
 	unsigned int cur_col, 
 				 cur_row, 
-				 idx, 
-				 new_idx,
 				 max_cols,
 				 max_rows;
+	CSV * new_csv;
+	char * content;
 	bool in_old, in_new;
 
-	/* add missing column cells */
-	new_table = malloc(sizeof(char *) * new_cols * new_rows);
+	/* Build a new (fake) csv */
+	new_csv = csv_create();
+	new_csv->rows = new_rows;
+	new_csv->cols = new_cols;
 
-	max_cols = (new_cols > csv->cols)? new_cols : csv->cols;
-	max_rows = (new_rows > csv->rows)? new_rows : csv->rows;
+	new_csv->table = malloc(sizeof(char *) * new_cols * new_rows);
+	memset(new_csv->table, 0, sizeof(char *) * new_cols * new_rows);
+
+	if (new_csv->table == NULL) { goto error; }
+
+	max_cols = (new_cols > old_csv->cols)? new_cols : old_csv->cols;
+	max_rows = (new_rows > old_csv->rows)? new_rows : old_csv->rows;
 
 	for (cur_col=0; cur_col<max_cols; cur_col++) {
 		for (cur_row=0; cur_row<max_rows; cur_row++) {
-			idx = cur_col + (cur_row * csv->cols);
-			new_idx = cur_col + (cur_row * new_cols);
-
-			in_old = (cur_col < csv->cols) && (cur_row < csv->rows);
-			in_new = (cur_col < new_cols) && (cur_row < new_rows);
+			in_old = (cur_col < old_csv->cols) && (cur_row < old_csv->rows);
+			in_new = (cur_col < new_csv->cols) && (cur_row < new_csv->rows);
 
 			if (in_old && in_new) {
 				/* re-link data */
-				new_table[new_idx] = csv->table[idx];
+				content = csv_get(old_csv, cur_col, cur_row);
+				csv_set(new_csv, cur_col, cur_row, content);
 			} else if (in_old) {
 				/* destroy data */
-				free(csv->table[idx]);
+				content = csv_get(old_csv, cur_col, cur_row);
+				free(content);
 			} else { 
-				/* set to NULL */
-				new_table[new_idx] = NULL;
+				/* skip */
+				/* csv_set(new_csv, cur_col, cur_row, NULL); */
 			}
 		}
 	}
 	/* on rows */		
-	free(csv->table);
-	csv->table = new_table;
+	free(old_csv->table);
+	old_csv->rows = new_rows;
+	old_csv->cols = new_cols;
+	old_csv->table = new_csv->table;
 	return 0;
+
+error:
+	printf("Unable to resize CSV table: error %d - %s\n", errno, strerror(errno));
+	return -1;
 }
 
 /* , char delim='\t' */
@@ -155,10 +182,6 @@ int csv_save(CSV * csv, char * filename) {
 	return 0;
 }
 
-int csv_set(CSV * csv, unsigned int col, unsigned int row, char * value) {
-	return 0;
-}
-
 int main(int argc, char ** argv) {
 	CSV * csv;