Implement multiline and hints support

[linenoise.git] / stringbuf.c

diff --git a/stringbuf.c b/stringbuf.c
new file mode 100644 (file)
index 0000000..acac04c
--- /dev/null
+++ b/stringbuf.c
@@ -0,0 +1,163 @@
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <assert.h>
+
+#include "stringbuf.h"
+#ifdef USE_UTF8
+#include "utf8.h"
+#endif
+
+#define SB_INCREMENT 200
+
+stringbuf *sb_alloc(void)
+{
+       stringbuf *sb = (stringbuf *)malloc(sizeof(*sb));
+       sb->remaining = 0;
+       sb->last = 0;
+#ifdef USE_UTF8
+       sb->chars = 0;
+#endif
+       sb->data = NULL;
+
+       return(sb);
+}
+
+void sb_free(stringbuf *sb)
+{
+       if (sb) {
+               free(sb->data);
+       }
+       free(sb);
+}
+
+void sb_realloc(stringbuf *sb, int newlen)
+{
+       sb->data = (char *)realloc(sb->data, newlen);
+       sb->remaining = newlen - sb->last;
+}
+
+void sb_append(stringbuf *sb, const char *str)
+{
+       sb_append_len(sb, str, strlen(str));
+}
+
+void sb_append_len(stringbuf *sb, const char *str, int len)
+{
+       int utf8_strlen(const char *str, int bytelen);
+       if (sb->remaining < len + 1) {
+               sb_realloc(sb, sb->last + len + 1 + SB_INCREMENT);
+       }
+       memcpy(sb->data + sb->last, str, len);
+       sb->data[sb->last + len] = 0;
+
+       sb->last += len;
+       sb->remaining -= len;
+#ifdef USE_UTF8
+       sb->chars += utf8_strlen(str, len);
+#endif
+}
+
+char *sb_to_string(stringbuf *sb)
+{
+       if (sb->data == NULL) {
+               /* Return an allocated empty string, not null */
+               return strdup("");
+       }
+       else {
+               /* Just return the data and free the stringbuf structure */
+               char *pt = sb->data;
+               free(sb);
+               return pt;
+       }
+}
+
+/* Insert and delete operations */
+
+/* Moves up all the data at position 'pos' and beyond by 'len' bytes
+ * to make room for new data
+ *
+ * Note: Does *not* update sb->chars
+ */
+static void sb_insert_space(stringbuf *sb, int pos, int len)
+{
+       assert(pos <= sb->last);
+
+       /* Make sure there is enough space */
+       if (sb->remaining < len) {
+               sb_realloc(sb, sb->last + len + SB_INCREMENT);
+       }
+       /* Now move it up */
+       memmove(sb->data + pos + len, sb->data + pos, sb->last - pos);
+       sb->last += len;
+       sb->remaining -= len;
+       /* And null terminate */
+       sb->data[sb->last] = 0;
+}
+
+/**
+ * Move down all the data from pos + len, effectively
+ * deleting the data at position 'pos' of length 'len'
+ */
+static void sb_delete_space(stringbuf *sb, int pos, int len)
+{
+       assert(pos < sb->last);
+       assert(pos + len <= sb->last);
+
+#ifdef USE_UTF8
+       sb->chars -= utf8_strlen(sb->data + pos, len);
+#endif
+
+       /* Now move it up */
+       memmove(sb->data + pos, sb->data + pos + len, sb->last - pos - len);
+       sb->last -= len;
+       sb->remaining += len;
+       /* And null terminate */
+       sb->data[sb->last] = 0;
+}
+
+void sb_insert(stringbuf *sb, int index, const char *str)
+{
+       if (index >= sb->last) {
+               /* Inserting after the end of the list appends. */
+               sb_append(sb, str);
+       }
+       else {
+               int len = strlen(str);
+
+               sb_insert_space(sb, index, len);
+               memcpy(sb->data + index, str, len);
+#ifdef USE_UTF8
+               sb->chars += utf8_strlen(str, len);
+#endif
+       }
+}
+
+/**
+ * Delete the bytes at index 'index' for length 'len'
+ * Has no effect if the index is past the end of the list.
+ */
+void sb_delete(stringbuf *sb, int index, int len)
+{
+       if (index < sb->last) {
+               char *pos = sb->data + index;
+               if (len < 0) {
+                       len = sb->last;
+               }
+
+               sb_delete_space(sb, pos - sb->data, len);
+       }
+}
+
+void sb_clear(stringbuf *sb)
+{
+       if (sb->data) {
+               /* Null terminate */
+               sb->data[0] = 0;
+               sb->last = 0;
+#ifdef USE_UTF8
+               sb->chars = 0;
+#endif
+       }
+}