1 files changed, 243 insertions, 0 deletions
diff --git a/strbuf.c b/strbuf.c
new file mode 100644
index 0000000..5efcfc8
--- /dev/null
+++ b/strbuf.c
@@ -0,0 +1,243 @@
+#include "cache.h"
+
+int prefixcmp(const char *str, const char *prefix)
+{
+	for (; ; str++, prefix++)
+		if (!*prefix)
+			return 0;
+		else if (*str != *prefix)
+			return (unsigned char)*prefix - (unsigned char)*str;
+}
+
+/*
+ * Used as the default ->buf value, so that people can always assume
+ * buf is non NULL and ->buf is NUL terminated even for a freshly
+ * initialized strbuf.
+ */
+char strbuf_slopbuf[1];
+
+void strbuf_init(struct strbuf *sb, size_t hint)
+{
+	sb->alloc = sb->len = 0;
+	sb->buf = strbuf_slopbuf;
+	if (hint)
+		strbuf_grow(sb, hint);
+}
+
+void strbuf_release(struct strbuf *sb)
+{
+	if (sb->alloc) {
+		free(sb->buf);
+		strbuf_init(sb, 0);
+	}
+}
+
+char *strbuf_detach(struct strbuf *sb, size_t *sz)
+{
+	char *res = sb->alloc ? sb->buf : NULL;
+	if (sz)
+		*sz = sb->len;
+	strbuf_init(sb, 0);
+	return res;
+}
+
+void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
+{
+	strbuf_release(sb);
+	sb->buf   = buf;
+	sb->len   = len;
+	sb->alloc = alloc;
+	strbuf_grow(sb, 0);
+	sb->buf[sb->len] = '\0';
+}
+
+void strbuf_grow(struct strbuf *sb, size_t extra)
+{
+	if (sb->len + extra + 1 <= sb->len)
+		die("you want to use way too much memory");
+	if (!sb->alloc)
+		sb->buf = NULL;
+	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
+}
+
+void strbuf_rtrim(struct strbuf *sb)
+{
+	while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
+		sb->len--;
+	sb->buf[sb->len] = '\0';
+}
+
+int strbuf_cmp(struct strbuf *a, struct strbuf *b)
+{
+	int cmp;
+	if (a->len < b->len) {
+		cmp = memcmp(a->buf, b->buf, a->len);
+		return cmp ? cmp : -1;
+	} else {
+		cmp = memcmp(a->buf, b->buf, b->len);
+		return cmp ? cmp : a->len != b->len;
+	}
+}
+
+void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
+				   const void *data, size_t dlen)
+{
+	if (pos + len < pos)
+		die("you want to use way too much memory");
+	if (pos > sb->len)
+		die("`pos' is too far after the end of the buffer");
+	if (pos + len > sb->len)
+		die("`pos + len' is too far after the end of the buffer");
+
+	if (dlen >= len)
+		strbuf_grow(sb, dlen - len);
+	memmove(sb->buf + pos + dlen,
+			sb->buf + pos + len,
+			sb->len - pos - len);
+	memcpy(sb->buf + pos, data, dlen);
+	strbuf_setlen(sb, sb->len + dlen - len);
+}
+
+void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
+{
+	strbuf_splice(sb, pos, 0, data, len);
+}
+
+void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
+{
+	strbuf_splice(sb, pos, len, NULL, 0);
+}
+
+void strbuf_add(struct strbuf *sb, const void *data, size_t len)
+{
+	strbuf_grow(sb, len);
+	memcpy(sb->buf + sb->len, data, len);
+	strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
+{
+	strbuf_grow(sb, len);
+	memcpy(sb->buf + sb->len, sb->buf + pos, len);
+	strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
+{
+	int len;
+	va_list ap;
+
+	if (!strbuf_avail(sb))
+		strbuf_grow(sb, 64);
+	va_start(ap, fmt);
+	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
+	va_end(ap);
+	if (len < 0)
+		die("your vsnprintf is broken");
+	if (len > strbuf_avail(sb)) {
+		strbuf_grow(sb, len);
+		va_start(ap, fmt);
+		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
+		va_end(ap);
+		if (len > strbuf_avail(sb)) {
+			die("this should not happen, your snprintf is broken");
+		}
+	}
+	strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_expand(struct strbuf *sb, const char *format,
+                   const char **placeholders, expand_fn_t fn, void *context)
+{
+	for (;;) {
+		const char *percent, **p;
+
+		percent = strchrnul(format, '%');
+		strbuf_add(sb, format, percent - format);
+		if (!*percent)
+			break;
+		format = percent + 1;
+
+		for (p = placeholders; *p; p++) {
+			if (!prefixcmp(format, *p))
+				break;
+		}
+		if (*p) {
+			fn(sb, *p, context);
+			format += strlen(*p);
+		} else
+			strbuf_addch(sb, '%');
+	}
+}
+
+size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
+{
+	size_t res;
+
+	strbuf_grow(sb, size);
+	res = fread(sb->buf + sb->len, 1, size, f);
+	if (res > 0) {
+		strbuf_setlen(sb, sb->len + res);
+	}
+	return res;
+}
+
+ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
+{
+	size_t oldlen = sb->len;
+
+	strbuf_grow(sb, hint ? hint : 8192);
+	for (;;) {
+		ssize_t cnt;
+
+		cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
+		if (cnt < 0) {
+			strbuf_setlen(sb, oldlen);
+			return -1;
+		}
+		if (!cnt)
+			break;
+		sb->len += cnt;
+		strbuf_grow(sb, 8192);
+	}
+
+	sb->buf[sb->len] = '\0';
+	return sb->len - oldlen;
+}
+
+int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
+{
+	int ch;
+
+	strbuf_grow(sb, 0);
+	if (feof(fp))
+		return EOF;
+
+	strbuf_reset(sb);
+	while ((ch = fgetc(fp)) != EOF) {
+		if (ch == term)
+			break;
+		strbuf_grow(sb, 1);
+		sb->buf[sb->len++] = ch;
+	}
+	if (ch == EOF && sb->len == 0)
+		return EOF;
+
+	sb->buf[sb->len] = '\0';
+	return 0;
+}
+
+int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
+{
+	int fd, len;
+
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		return -1;
+	len = strbuf_read(sb, fd, hint);
+	close(fd);
+	if (len < 0)
+		return -1;
+
+	return len;
+}