yank buffer and initial copy/cut/paste support

1 files changed, 117 insertions, 0 deletions

diff --git a/lineset.c b/lineset.c
new file mode 100644
index 0000000..faabb30
--- /dev/null
+++ b/lineset.c
@@ -0,0 +1,117 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "gramscii.h"
+
+static int LONG_STEP;
+
+/* line_t and lineset_t management */
+
+void ensure_line_length(line_t *l, int len){
+	char *tmp;
+
+	if (l->sz < len + 1){
+		tmp = realloc(l->s, (len+1) * 2 * sizeof(char));
+		if (!tmp){
+			fprintf(stderr, "Unable to allocate string\n");
+			exit(1);
+		}
+		l->s = tmp;
+		l->sz = (len + 1) * 2;
+	}
+}
+
+
+void alloc_line(line_t *l){
+	char *tmp;
+
+	l->sz = WIDTH+1;
+	tmp = malloc((l->sz) * sizeof(char));
+	if (tmp == NULL){
+		fprintf(stderr, "unable to allocate line\n");
+		exit(1);
+	}
+	l->s = tmp;
+	memset(l->s, BG, l->sz);
+	l->lst = -1;
+	l->s[0]='\0';
+}
+
+void ensure_num_lines(lineset_t *ls, int n){
+	line_t *tmp;
+
+	if (n > ls->sz){
+		if (ls->sz == 0)
+			ls->l=NULL;
+		tmp = realloc(ls->l, (n + LONG_STEP) * sizeof(line_t));
+		if (tmp == NULL){
+			fprintf(stderr, "Unable to allocate memory for more lines");
+			exit(1);
+		}
+		else {
+			ls->l = tmp;
+			while ( ls->sz < n + LONG_STEP){
+				alloc_line(&(ls->l[ls->sz]));
+				ls->sz ++;
+			}
+		}
+	}
+}
+
+void dump_lines(lineset_t ls, FILE *f){
+	int i;
+	for (i=0; i<ls.num ;i++){
+		fprintf(f, "%d:%s\n", i, ls.l[i].s);
+	}
+	fflush(f);
+}
+
+void pad_line_to_length(char *s, int W){
+
+	int i;
+
+	for (i=strlen(s); i<W; i++){
+		s[i] = BG;
+	}
+}
+
+/* cut/yank/paste/undo management */
+
+void yank_region(int x1, int y1, int x2, int y2){
+
+	int N, W, i;
+
+	N = y2 - y1 + 1;
+	W = x2 - x1 + 1;
+	ensure_num_lines(&cutbuf, N);
+	
+	for (i=y1; i<=y2; i++){
+		ensure_line_length(&(cutbuf.l[i-y1]), W);
+		memcpy(cutbuf.l[i-y1].s, screen.l[i].s + x1, x2-x1+1);
+		if (strlen(cutbuf.l[i-y1].s) < W)
+			pad_line_to_length(cutbuf.l[i-y1].s, W);
+		cutbuf.l[i-y1].s[W] = '\0';
+		cutbuf.l[i-y1].n = i;
+	}
+	cutbuf.num = N;
+#ifdef DEBUG
+	dump_lines(cutbuf, stderr);
+#endif
+	
+}
+
+
+void paste_region(int x1, int y1){
+	int i, curlen;
+
+	i = y1;
+	while( i < HEIGHT && i < y1 + cutbuf.num){
+		memcpy(screen.l[i].s + x1, cutbuf.l[i-y1].s, strlen(cutbuf.l[i-y1].s));
+		curlen = strlen(screen.l[i].s); 
+		if (curlen <= x1)
+			/* double-check this line below */
+			pad_line_to_length(screen.l[i].s+curlen, x1 - curlen);
+		i += 1;
+		modified = 1;
+	}
+}