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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /tools/perf/util/strbuf.c
Initial import
Diffstat (limited to 'tools/perf/util/strbuf.c')
-rw-r--r--tools/perf/util/strbuf.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/tools/perf/util/strbuf.c b/tools/perf/util/strbuf.c
new file mode 100644
index 000000000..4abe23550
--- /dev/null
+++ b/tools/perf/util/strbuf.c
@@ -0,0 +1,134 @@
+#include "cache.h"
+#include <linux/kernel.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, ssize_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) {
+ zfree(&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_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);
+}
+
+static 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_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_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 vsnprintf is broken");
+ }
+ }
+ strbuf_setlen(sb, sb->len + len);
+}
+
+ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
+{
+ size_t oldlen = sb->len;
+ size_t oldalloc = sb->alloc;
+
+ strbuf_grow(sb, hint ? hint : 8192);
+ for (;;) {
+ ssize_t cnt;
+
+ cnt = read(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
+ if (cnt < 0) {
+ if (oldalloc == 0)
+ strbuf_release(sb);
+ else
+ 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;
+}