Add strbuf API

Shamelessly stolen from Git.
pull/5/head
Michael Spang 14 years ago
parent 235b223e4b
commit f5a71b6b32
  1. 435
      src/strbuf.c
  2. 158
      src/strbuf.h

@ -0,0 +1,435 @@
/*
Copyright (c) 2005-2008 Junio C. Hamano et al.
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.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <fcntl.h>
#include "strbuf.h"
#include "util.h"
#define die fatal
#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)
static inline char *gitstrchrnul(const char *s, int c)
{
while (*s && *s != c)
s++;
return (char *)s;
}
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_trim(struct strbuf *sb)
{
char *b = sb->buf;
while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
sb->len--;
while (sb->len > 0 && isspace(*b)) {
b++;
sb->len--;
}
memmove(sb->buf, b, sb->len);
sb->buf[sb->len] = '\0';
}
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_ltrim(struct strbuf *sb)
{
char *b = sb->buf;
while (sb->len > 0 && isspace(*b)) {
b++;
sb->len--;
}
memmove(sb->buf, b, sb->len);
sb->buf[sb->len] = '\0';
}
void strbuf_tolower(struct strbuf *sb)
{
int i;
for (i = 0; i < sb->len; i++)
sb->buf[i] = tolower(sb->buf[i]);
}
struct strbuf **strbuf_split(const struct strbuf *sb, int delim)
{
int alloc = 2, pos = 0;
char *n, *p;
struct strbuf **ret;
struct strbuf *t;
ret = xcalloc(alloc, sizeof(struct strbuf *));
p = n = sb->buf;
while (n < sb->buf + sb->len) {
int len;
n = memchr(n, delim, sb->len - (n - sb->buf));
if (pos + 1 >= alloc) {
alloc = alloc * 2;
ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
}
if (!n)
n = sb->buf + sb->len - 1;
len = n - p + 1;
t = xmalloc(sizeof(struct strbuf));
strbuf_init(t, len);
strbuf_add(t, p, len);
ret[pos] = t;
ret[++pos] = NULL;
p = ++n;
}
return ret;
}
struct strbuf **strbuf_splitws(const struct strbuf *sb)
{
int alloc = 2, pos = 0;
struct strbuf **ret;
int prev_ws = 1, ws;
int i, start = 0;
ret = xcalloc(alloc, sizeof(struct strbuf *));
for (i = 0; i <= sb->len; i++) {
ws = !sb->buf[i] || isspace(sb->buf[i]);
if (prev_ws == ws)
continue;
if (!ws) {
start = i;
} else {
if (pos + 1 >= alloc) {
alloc = alloc * 2;
ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
}
ret[pos] = xmalloc(sizeof(struct strbuf));
strbuf_init(ret[pos], i - start);
strbuf_add(ret[pos], &sb->buf[start], i - start);
pos++;
}
prev_ws = ws;
}
ret[pos] = NULL;
return ret;
}
void strbuf_list_free(struct strbuf **sbs)
{
struct strbuf **s = sbs;
while (*s) {
strbuf_release(*s);
free(*s++);
}
free(sbs);
}
size_t strbuf_list_len(struct strbuf **sbs)
{
size_t n = 0;
while (*sbs++)
n++;
return n;
}
int strbuf_cmp(const struct strbuf *a, const 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, expand_fn_t fn,
void *context)
{
for (;;) {
const char *percent;
size_t consumed;
percent = gitstrchrnul(format, '%');
strbuf_add(sb, format, percent - format);
if (!*percent)
break;
format = percent + 1;
consumed = fn(sb, format, context);
if (consumed)
format += consumed;
else
strbuf_addch(sb, '%');
}
}
size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
void *context)
{
struct strbuf_expand_dict_entry *e = context;
size_t len;
for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
if (!strncmp(placeholder, e->placeholder, len)) {
if (e->value)
strbuf_addstr(sb, e->value);
return len;
}
}
return 0;
}
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_write(struct strbuf *sb, int fd) {
ssize_t total = 0;
while (total < sb->len) {
ssize_t cnt = write(fd, sb->buf + total, sb->len - total);
if (cnt <= 0)
return -1;
total += cnt;
}
return total;
}
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 = read(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;
}

@ -0,0 +1,158 @@
/*
Copyright (c) 2005-2008 Junio C. Hamano et al.
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.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef STRBUF_H
#define STRBUF_H
/*
* Strbuf's can be use in many ways: as a byte array, or to store arbitrary
* long, overflow safe strings.
*
* Strbufs has some invariants that are very important to keep in mind:
*
* 1. the ->buf member is always malloc-ed, hence strbuf's can be used to
* build complex strings/buffers whose final size isn't easily known.
*
* It is NOT legal to copy the ->buf pointer away.
* `strbuf_detach' is the operation that detachs a buffer from its shell
* while keeping the shell valid wrt its invariants.
*
* 2. the ->buf member is a byte array that has at least ->len + 1 bytes
* allocated. The extra byte is used to store a '\0', allowing the ->buf
* member to be a valid C-string. Every strbuf function ensure this
* invariant is preserved.
*
* Note that it is OK to "play" with the buffer directly if you work it
* that way:
*
* strbuf_grow(sb, SOME_SIZE);
* ... Here, the memory array starting at sb->buf, and of length
* ... strbuf_avail(sb) is all yours, and you are sure that
* ... strbuf_avail(sb) is at least SOME_SIZE.
* strbuf_setlen(sb, sb->len + SOME_OTHER_SIZE);
*
* Of course, SOME_OTHER_SIZE must be smaller or equal to strbuf_avail(sb).
*
* Doing so is safe, though if it has to be done in many places, adding the
* missing API to the strbuf module is the way to go.
*
* XXX: do _not_ assume that the area that is yours is of size ->alloc - 1
* even if it's true in the current implementation. Alloc is somehow a
* "private" member that should not be messed with.
*/
#include <assert.h>
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
extern char strbuf_slopbuf[];
struct strbuf {
size_t alloc;
size_t len;
char *buf;
};
#define STRBUF_INIT { 0, 0, strbuf_slopbuf }
/*----- strbuf life cycle -----*/
extern void strbuf_init(struct strbuf *, size_t);
extern void strbuf_release(struct strbuf *);
extern char *strbuf_detach(struct strbuf *, size_t *);
extern void strbuf_attach(struct strbuf *, void *, size_t, size_t);
static inline void strbuf_swap(struct strbuf *a, struct strbuf *b) {
struct strbuf tmp = *a;
*a = *b;
*b = tmp;
}
/*----- strbuf size related -----*/
static inline size_t strbuf_avail(const struct strbuf *sb) {
return sb->alloc ? sb->alloc - sb->len - 1 : 0;
}
extern void strbuf_grow(struct strbuf *, size_t);
static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
if (!sb->alloc)
strbuf_grow(sb, 0);
assert(len < sb->alloc);
sb->len = len;
sb->buf[len] = '\0';
}
#define strbuf_reset(sb) strbuf_setlen(sb, 0)
/*----- content related -----*/
extern void strbuf_trim(struct strbuf *);
extern void strbuf_rtrim(struct strbuf *);
extern void strbuf_ltrim(struct strbuf *);
extern int strbuf_cmp(const struct strbuf *, const struct strbuf *);
extern void strbuf_tolower(struct strbuf *);
extern struct strbuf **strbuf_split(const struct strbuf *, int delim);
extern struct strbuf **strbuf_splitws(const struct strbuf *);
extern void strbuf_list_free(struct strbuf **);
extern size_t strbuf_list_len(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';
}
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, const struct strbuf *sb2) {
strbuf_add(sb, sb2->buf, sb2->len);
}
extern void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len);
typedef size_t (*expand_fn_t) (struct strbuf *sb, const char *placeholder, void *context);
extern void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn, void *context);
struct strbuf_expand_dict_entry {
const char *placeholder;
const char *value;
};
extern size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder, void *context);
__attribute__((format(printf,2,3)))
extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
extern void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap);
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);
extern ssize_t strbuf_write(struct strbuf *sb, int fd);
extern int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint);
extern int strbuf_getline(struct strbuf *, FILE *, int);
extern void stripspace(struct strbuf *buf, int skip_comments);
extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
#endif /* STRBUF_H */
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