sudoku: add line-grid parsing

src/sudoku.c

@@ -1,6 +1,7 @@
 #include "sudoku.h"
 
 #include <stdio.h>
+#include <stdlib.h>
 
 #define INPUT_PATTERN "%1d %1d %1d %1d %1d %1d %1d %1d %1d\n"
 
@@ -35,3 +36,37 @@ bool parse_grid_str(struct sudoku *grid, const char *input) {
 
     return true;
 }
+
+bool parse_line_file(struct sudoku *grid, FILE *input) {
+    if (!input || !grid)
+        return false;
+
+    char *line = NULL;
+    if (getline(&line, NULL, input) < 0)
+        return false;
+
+    bool ret = parse_line_str(grid, line);
+
+    free(line);
+
+    return ret;
+}
+
+bool parse_line_str(struct sudoku *grid, const char *input) {
+    if (!input || !grid)
+        return false;
+
+    for (size_t i = 0; i < 9; ++i) {
+        for (size_t j = 0; j < 9; ++j) {
+            char c = *(input++);
+            if (c >= '1' && c <= '9')
+                grid->grid[i][j] = c - '0';
+            else if (c == '.' || c == '0')
+                grid->grid[i][j] = 0;
+            else
+                return false;
+        }
+    }
+
+    return true;
+}

src/sudoku.h

@@ -10,5 +10,7 @@ struct sudoku {
 
 bool parse_grid_file(struct sudoku *grid, FILE *input);
 bool parse_grid_str(struct sudoku *grid, const char *input);
+bool parse_line_file(struct sudoku *grid, FILE *input);
+bool parse_line_str(struct sudoku *grid, const char *input);
 
 #endif /* !SUDOKU_H */