[Sheepdog] [PATCH 4/5] sheep: add string buf candy helpers
Liu Yuan
namei.unix at gmail.com
Tue Nov 15 04:16:45 CET 2011
From: Liu Yuan <tailai.ly at taobao.com>
This is almost taken from git. Thank git if you find it useful.
Signed-off-by: Liu Yuan <tailai.ly at taobao.com>
---
sheep/strbuf.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
sheep/strbuf.h | 95 ++++++++++++++++++++++++++++
2 files changed, 287 insertions(+), 0 deletions(-)
create mode 100644 sheep/strbuf.c
create mode 100644 sheep/strbuf.h
diff --git a/sheep/strbuf.c b/sheep/strbuf.c
new file mode 100644
index 0000000..1caaa42
--- /dev/null
+++ b/sheep/strbuf.c
@@ -0,0 +1,192 @@
+/* Taken from git by Liu Yuan <namei.unix at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "strbuf.h"
+#include "logger.h"
+
+void strbuf_init(struct strbuf *sb, size_t hint)
+{
+ memset(sb, 0, sizeof(*sb));
+ if (hint)
+ strbuf_grow(sb, hint);
+}
+
+void strbuf_release(struct strbuf *sb)
+{
+ free(sb->buf);
+ memset(sb, 0, sizeof(*sb));
+}
+
+void strbuf_reset(struct strbuf *sb)
+{
+ if (sb->len)
+ strbuf_setlen(sb, 0);
+ sb->eof = 0;
+}
+
+char *strbuf_detach(struct strbuf *sb)
+{
+ char *res = sb->buf;
+ 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)
+ panic("you want to use way too much memory");
+ 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';
+}
+
+void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
+{
+ strbuf_grow(sb, len);
+ if (pos > sb->len)
+ panic("`pos' is too far after the end of the buffer");
+ memmove(sb->buf + pos + len, sb->buf + pos, sb->len - pos);
+ memcpy(sb->buf + pos, data, len);
+ strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
+ const void *data, size_t dlen)
+{
+ if (pos + len < pos)
+ panic("you want to use way too much memory");
+ if (pos > sb->len)
+ panic("`pos' is too far after the end of the buffer");
+ if (pos + len > sb->len)
+ panic("`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;
+
+ va_start(ap, fmt);
+ len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
+ va_end(ap);
+ if (len < 0) {
+ len = 0;
+ }
+ 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)) {
+ panic("this should not happen, your snprintf is broken");
+ }
+ }
+ strbuf_setlen(sb, sb->len + len);
+}
+
+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;
+}
+
+static int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
+{
+ int ch;
+
+ if (feof(fp))
+ return EOF;
+
+ strbuf_reset(sb);
+ while ((ch = fgetc(fp)) != EOF) {
+ strbuf_grow(sb, 1);
+ sb->buf[sb->len++] = ch;
+ if (ch == term)
+ break;
+ }
+ if (ch == EOF && sb->len == 0)
+ return EOF;
+
+ sb->buf[sb->len] = '\0';
+ return 0;
+}
+
+int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
+{
+ if (strbuf_getwholeline(sb, fp, term))
+ return EOF;
+ if (sb->buf[sb->len-1] == term)
+ strbuf_setlen(sb, sb->len-1);
+ return 0;
+}
diff --git a/sheep/strbuf.h b/sheep/strbuf.h
new file mode 100644
index 0000000..573784b
--- /dev/null
+++ b/sheep/strbuf.h
@@ -0,0 +1,95 @@
+#ifndef STRBUF_H
+#define STRBUF_H
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "util.h"
+
+struct strbuf {
+ size_t alloc;
+ size_t len;
+ int eof;
+ char *buf;
+};
+
+#define alloc_nr(x) (((x)+16)*3/2)
+
+/*
+ * Realloc the buffer pointed at by variable 'x' so that it can hold
+ * at least 'nr' entries; the number of entries currently allocated
+ * is 'alloc', using the standard growing factor alloc_nr() macro.
+ *
+ * DO NOT USE any expression with side-effect for 'x' or 'alloc'.
+ */
+#define ALLOC_GROW(x, nr, alloc) \
+ do { \
+ if ((nr) > alloc) { \
+ if (alloc_nr(alloc) < (nr)) \
+ alloc = (nr); \
+ else \
+ alloc = alloc_nr(alloc); \
+ x = xrealloc((x), alloc * sizeof(*(x))); \
+ } \
+ } while(0)
+
+#define STRBUF_INIT { 0, 0, 0, NULL }
+
+/*----- strbuf life cycle -----*/
+extern void strbuf_init(struct strbuf *, size_t);
+extern void strbuf_release(struct strbuf *);
+extern void strbuf_reset(struct strbuf *);
+extern char *strbuf_detach(struct strbuf *);
+extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
+
+/*----- strbuf size related -----*/
+static inline size_t strbuf_avail(struct strbuf *sb) {
+ return sb->alloc ? sb->alloc - sb->len - 1 : 0;
+}
+static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
+ assert (len < sb->alloc);
+ sb->len = len;
+ sb->buf[len] = '\0';
+}
+
+extern void strbuf_grow(struct strbuf *, size_t);
+
+/*----- content related -----*/
+extern void strbuf_rtrim(struct strbuf *);
+
+/*----- add data in your buffer -----*/
+static inline void strbuf_addch(struct strbuf *sb, int c) {
+ strbuf_grow(sb, 1);
+ sb->buf[sb->len++] = c;
+ sb->buf[sb->len] = '\0';
+}
+
+/* inserts after pos, or appends if pos >= sb->len */
+extern void strbuf_insert(struct strbuf *, size_t pos, const void *, size_t);
+extern void strbuf_remove(struct strbuf *, size_t pos, size_t len);
+
+/* splice pos..pos+len with given data */
+extern void strbuf_splice(struct strbuf *, size_t pos, size_t len,
+ const void *, size_t);
+
+extern void strbuf_add(struct strbuf *, const void *, size_t);
+static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
+ strbuf_add(sb, s, strlen(s));
+}
+static inline void strbuf_addbuf(struct strbuf *sb, struct strbuf *sb2) {
+ strbuf_add(sb, sb2->buf, sb2->len);
+}
+
+__attribute__((format(printf,2,3)))
+extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
+
+extern size_t strbuf_fread(struct strbuf *, size_t, FILE *);
+/* XXX: if read fails, any partial read is undone */
+extern ssize_t strbuf_read(struct strbuf *, int fd, size_t hint);
+int strbuf_getline(struct strbuf *sb, FILE *fp, int term);
+
+#endif
--
1.7.6.1
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