git/quote.c
Pierre Habouzit 7a33bcbe80 sq_quote_argv and add_to_string rework with strbuf's.
* sq_quote_buf is made public, and works on a strbuf.
* sq_quote_argv also works on a strbuf.
* make sq_quote_argv take a "maxlen" argument to check the buffer won't grow
  too big.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-21 03:31:18 -07:00

394 lines
8.5 KiB
C

#include "cache.h"
#include "quote.h"
/* Help to copy the thing properly quoted for the shell safety.
* any single quote is replaced with '\'', any exclamation point
* is replaced with '\!', and the whole thing is enclosed in a
*
* E.g.
* original sq_quote result
* name ==> name ==> 'name'
* a b ==> a b ==> 'a b'
* a'b ==> a'\''b ==> 'a'\''b'
* a!b ==> a'\!'b ==> 'a'\!'b'
*/
static inline int need_bs_quote(char c)
{
return (c == '\'' || c == '!');
}
void sq_quote_buf(struct strbuf *dst, const char *src)
{
char *to_free = NULL;
if (dst->buf == src)
to_free = strbuf_detach(dst);
strbuf_addch(dst, '\'');
while (*src) {
size_t len = strcspn(src, "'\\");
strbuf_add(dst, src, len);
src += len;
while (need_bs_quote(*src)) {
strbuf_addstr(dst, "'\\");
strbuf_addch(dst, *src++);
strbuf_addch(dst, '\'');
}
}
strbuf_addch(dst, '\'');
free(to_free);
}
void sq_quote_print(FILE *stream, const char *src)
{
char c;
fputc('\'', stream);
while ((c = *src++)) {
if (need_bs_quote(c)) {
fputs("'\\", stream);
fputc(c, stream);
fputc('\'', stream);
} else {
fputc(c, stream);
}
}
fputc('\'', stream);
}
void sq_quote_argv(struct strbuf *dst, const char** argv, int count,
size_t maxlen)
{
int i;
/* Count argv if needed. */
if (count < 0) {
for (count = 0; argv[count]; count++)
; /* just counting */
}
/* Copy into destination buffer. */
strbuf_grow(dst, 32 * count);
for (i = 0; i < count; ++i) {
strbuf_addch(dst, ' ');
sq_quote_buf(dst, argv[i]);
if (maxlen && dst->len > maxlen)
die("Too many or long arguments");
}
}
char *sq_dequote(char *arg)
{
char *dst = arg;
char *src = arg;
char c;
if (*src != '\'')
return NULL;
for (;;) {
c = *++src;
if (!c)
return NULL;
if (c != '\'') {
*dst++ = c;
continue;
}
/* We stepped out of sq */
switch (*++src) {
case '\0':
*dst = 0;
return arg;
case '\\':
c = *++src;
if (need_bs_quote(c) && *++src == '\'') {
*dst++ = c;
continue;
}
/* Fallthrough */
default:
return NULL;
}
}
}
/* 1 means: quote as octal
* 0 means: quote as octal if (quote_path_fully)
* -1 means: never quote
* c: quote as "\\c"
*/
#define X8(x) x, x, x, x, x, x, x, x
#define X16(x) X8(x), X8(x)
static signed char const sq_lookup[256] = {
/* 0 1 2 3 4 5 6 7 */
/* 0x00 */ 1, 1, 1, 1, 1, 1, 1, 'a',
/* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r', 1, 1,
/* 0x10 */ X16(1),
/* 0x20 */ -1, -1, '"', -1, -1, -1, -1, -1,
/* 0x28 */ X16(-1), X16(-1), X16(-1),
/* 0x58 */ -1, -1, -1, -1,'\\', -1, -1, -1,
/* 0x60 */ X16(-1), X8(-1),
/* 0x78 */ -1, -1, -1, -1, -1, -1, -1, 1,
/* 0x80 */ /* set to 0 */
};
static inline int sq_must_quote(char c) {
return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
}
/* returns the longest prefix not needing a quote up to maxlen if positive.
This stops at the first \0 because it's marked as a character needing an
escape */
static size_t next_quote_pos(const char *s, ssize_t maxlen)
{
size_t len;
if (maxlen < 0) {
for (len = 0; !sq_must_quote(s[len]); len++);
} else {
for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
}
return len;
}
/*
* C-style name quoting.
*
* (1) if sb and fp are both NULL, inspect the input name and counts the
* number of bytes that are needed to hold c_style quoted version of name,
* counting the double quotes around it but not terminating NUL, and
* returns it.
* However, if name does not need c_style quoting, it returns 0.
*
* (2) if sb or fp are not NULL, it emits the c_style quoted version
* of name, enclosed with double quotes if asked and needed only.
* Return value is the same as in (1).
*/
static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
struct strbuf *sb, FILE *fp, int no_dq)
{
#undef EMIT
#define EMIT(c) \
do { \
if (sb) strbuf_addch(sb, (c)); \
if (fp) fputc((c), fp); \
count++; \
} while (0)
#define EMITBUF(s, l) \
do { \
if (sb) strbuf_add(sb, (s), (l)); \
if (fp) fwrite((s), (l), 1, fp); \
count += (l); \
} while (0)
size_t len, count = 0;
const char *p = name;
for (;;) {
int ch;
len = next_quote_pos(p, maxlen);
if (len == maxlen || !p[len])
break;
if (!no_dq && p == name)
EMIT('"');
EMITBUF(p, len);
EMIT('\\');
p += len;
ch = (unsigned char)*p++;
if (sq_lookup[ch] >= ' ') {
EMIT(sq_lookup[ch]);
} else {
EMIT(((ch >> 6) & 03) + '0');
EMIT(((ch >> 3) & 07) + '0');
EMIT(((ch >> 0) & 07) + '0');
}
}
EMITBUF(p, len);
if (p == name) /* no ending quote needed */
return 0;
if (!no_dq)
EMIT('"');
return count;
}
size_t quote_c_style(const char *name, struct strbuf *sb, FILE *fp, int nodq)
{
return quote_c_style_counted(name, -1, sb, fp, nodq);
}
void write_name_quoted(const char *name, FILE *fp, int terminator)
{
if (terminator) {
quote_c_style(name, NULL, fp, 0);
} else {
fputs(name, fp);
}
fputc(terminator, fp);
}
extern void write_name_quotedpfx(const char *pfx, size_t pfxlen,
const char *name, FILE *fp, int terminator)
{
int needquote = 0;
if (terminator) {
needquote = next_quote_pos(pfx, pfxlen) < pfxlen
|| name[next_quote_pos(name, -1)];
}
if (needquote) {
fputc('"', fp);
quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
quote_c_style(name, NULL, fp, 1);
fputc('"', fp);
} else {
fwrite(pfx, pfxlen, 1, fp);
fputs(name, fp);
}
fputc(terminator, fp);
}
/*
* C-style name unquoting.
*
* Quoted should point at the opening double quote.
* + Returns 0 if it was able to unquote the string properly, and appends the
* result in the strbuf `sb'.
* + Returns -1 in case of error, and doesn't touch the strbuf. Though note
* that this function will allocate memory in the strbuf, so calling
* strbuf_release is mandatory whichever result unquote_c_style returns.
*
* Updates endp pointer to point at one past the ending double quote if given.
*/
int unquote_c_style(struct strbuf *sb, const char *quoted, const char **endp)
{
size_t oldlen = sb->len, len;
int ch, ac;
if (*quoted++ != '"')
return -1;
for (;;) {
len = strcspn(quoted, "\"\\");
strbuf_add(sb, quoted, len);
quoted += len;
switch (*quoted++) {
case '"':
if (endp)
*endp = quoted + 1;
return 0;
case '\\':
break;
default:
goto error;
}
switch ((ch = *quoted++)) {
case 'a': ch = '\a'; break;
case 'b': ch = '\b'; break;
case 'f': ch = '\f'; break;
case 'n': ch = '\n'; break;
case 'r': ch = '\r'; break;
case 't': ch = '\t'; break;
case 'v': ch = '\v'; break;
case '\\': case '"':
break; /* verbatim */
/* octal values with first digit over 4 overflow */
case '0': case '1': case '2': case '3':
ac = ((ch - '0') << 6);
if ((ch = *quoted++) < '0' || '7' < ch)
goto error;
ac |= ((ch - '0') << 3);
if ((ch = *quoted++) < '0' || '7' < ch)
goto error;
ac |= (ch - '0');
ch = ac;
break;
default:
goto error;
}
strbuf_addch(sb, ch);
}
error:
strbuf_setlen(sb, oldlen);
return -1;
}
/* quoting as a string literal for other languages */
void perl_quote_print(FILE *stream, const char *src)
{
const char sq = '\'';
const char bq = '\\';
char c;
fputc(sq, stream);
while ((c = *src++)) {
if (c == sq || c == bq)
fputc(bq, stream);
fputc(c, stream);
}
fputc(sq, stream);
}
void python_quote_print(FILE *stream, const char *src)
{
const char sq = '\'';
const char bq = '\\';
const char nl = '\n';
char c;
fputc(sq, stream);
while ((c = *src++)) {
if (c == nl) {
fputc(bq, stream);
fputc('n', stream);
continue;
}
if (c == sq || c == bq)
fputc(bq, stream);
fputc(c, stream);
}
fputc(sq, stream);
}
void tcl_quote_print(FILE *stream, const char *src)
{
char c;
fputc('"', stream);
while ((c = *src++)) {
switch (c) {
case '[': case ']':
case '{': case '}':
case '$': case '\\': case '"':
fputc('\\', stream);
default:
fputc(c, stream);
break;
case '\f':
fputs("\\f", stream);
break;
case '\r':
fputs("\\r", stream);
break;
case '\n':
fputs("\\n", stream);
break;
case '\t':
fputs("\\t", stream);
break;
case '\v':
fputs("\\v", stream);
break;
}
}
fputc('"', stream);
}