git/quote.c

456 lines
9.9 KiB
C
Raw Normal View History

#include "cache.h"
#include "quote.h"
#include "argv-array.h"
int quote_path_fully = 1;
static inline int need_bs_quote(char c)
{
return (c == '\'' || c == '!');
}
/* 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
* single quote pair.
*
* 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'
*/
void sq_quote_buf(struct strbuf *dst, const char *src)
{
char *to_free = NULL;
if (dst->buf == src)
to_free = strbuf_detach(dst, NULL);
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_quotef(struct strbuf *dst, const char *fmt, ...)
{
struct strbuf src = STRBUF_INIT;
va_list ap;
va_start(ap, fmt);
strbuf_vaddf(&src, fmt, ap);
va_end(ap);
sq_quote_buf(dst, src.buf);
strbuf_release(&src);
}
void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
{
int i;
/* Copy into destination buffer. */
strbuf_grow(dst, 255);
for (i = 0; argv[i]; ++i) {
strbuf_addch(dst, ' ');
sq_quote_buf(dst, argv[i]);
if (maxlen && dst->len > maxlen)
die("Too many or long arguments");
}
}
static char *sq_dequote_step(char *arg, char **next)
{
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;
if (next)
*next = NULL;
return arg;
case '\\':
c = *++src;
if (need_bs_quote(c) && *++src == '\'') {
*dst++ = c;
continue;
}
/* Fallthrough */
default:
if (!next || !isspace(*src))
return NULL;
do {
c = *++src;
} while (isspace(c));
*dst = 0;
*next = src;
return arg;
}
}
}
char *sq_dequote(char *arg)
{
return sq_dequote_step(arg, NULL);
}
static int sq_dequote_to_argv_internal(char *arg,
const char ***argv, int *nr, int *alloc,
struct argv_array *array)
{
char *next = arg;
if (!*arg)
return 0;
do {
char *dequoted = sq_dequote_step(next, &next);
if (!dequoted)
return -1;
if (argv) {
ALLOC_GROW(*argv, *nr + 1, *alloc);
(*argv)[(*nr)++] = dequoted;
}
if (array)
argv_array_push(array, dequoted);
} while (next);
return 0;
}
int sq_dequote_to_argv(char *arg, const char ***argv, int *nr, int *alloc)
{
return sq_dequote_to_argv_internal(arg, argv, nr, alloc, NULL);
}
int sq_dequote_to_argv_array(char *arg, struct argv_array *array)
{
return sq_dequote_to_argv_internal(arg, NULL, NULL, NULL, array);
}
/* 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 || (maxlen < 0 && !p[len]))
break;
if (!no_dq && p == name)
EMIT('"');
EMITBUF(p, len);
EMIT('\\');
p += len;
ch = (unsigned char)*p++;
if (maxlen >= 0)
maxlen -= len + 1;
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 quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path, int nodq)
{
if (quote_c_style(prefix, NULL, NULL, 0) ||
quote_c_style(path, NULL, NULL, 0)) {
if (!nodq)
strbuf_addch(sb, '"');
quote_c_style(prefix, sb, NULL, 1);
quote_c_style(path, sb, NULL, 1);
if (!nodq)
strbuf_addch(sb, '"');
} else {
strbuf_addstr(sb, prefix);
strbuf_addstr(sb, path);
}
}
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);
}
void write_name_quoted_relative(const char *name, const char *prefix,
FILE *fp, int terminator)
{
struct strbuf sb = STRBUF_INIT;
quote.c: substitute path_relative with relative_path Substitute the function path_relative in quote.c with the function relative_path. Function relative_path can be treated as an enhanced and more robust version of path_relative. Outputs of path_relative and it's replacement (relative_path) are the same for the following cases: path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/c/ /a/b/ c/ c/ /a/b/c /a/b/ c c /a/ /a/b/ ../ ../ / /a/b/ ../../ ../../ /a/c /a/b/ ../c ../c /x/y /a/b/ ../../x/y ../../x/y a/b/c/ a/b/ c/ c/ a/ a/b/ ../ ../ x/y a/b/ ../../x/y ../../x/y /a/b (empty) /a/b /a/b /a/b (null) /a/b /a/b a/b (empty) a/b a/b a/b (null) a/b a/b But if both of the path and the prefix are the same, or the returned relative path should be the current directory, the outputs of both functions are different. Function relative_path returns "./", while function path_relative returns empty string. path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/ /a/b/ (empty) ./ a/b/ a/b/ (empty) ./ (empty) (null) (empty) ./ (empty) (empty) (empty) ./ But the callers of path_relative can handle such cases, or never encounter this issue at all, because: * In function quote_path_relative, if the output of path_relative is empty, append "./" to it, like: if (!out->len) strbuf_addstr(out, "./"); * Another caller is write_name_quoted_relative, which is only used by builtin/ls-files.c. git-ls-files only show files, so path of files will never be identical with the prefix of a directory. The following differences show that path_relative does not handle extra slashes properly: path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a//b//c/ //a/b// ../../../../a//b//c/ c/ a/b//c a//b ../b//c c And if prefix has no trailing slash, path_relative does not work properly either. But since prefix always has a trailing slash, it's not a problem. path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/c/ /a/b b/c/ c/ /a/b /a/b b ./ /a/b/ /a/b b/ ./ /a /a/b/ ../../a ../ a/b/c/ a/b b/c/ c/ a/b/ a/b b/ ./ a a/b ../a ../ x/y a/b/ ../x/y ../../x/y a/c a/b c ../c /a/ /a/b (empty) ../ (empty) /a/b ../../ ./ One tricky part in this conversion is write_name() function in ls-files.c. It takes a counted string, <name, len>, that is to be made relative to <prefix, prefix_len> and then quoted. Because write_name_quoted_relative() still takes these two parameters as counted string, but ignores the count and treat these two as NUL-terminated strings, this conversion needs to be audited for its callers: - For <name, len>, all three callers of write_name() passes a NUL-terminated string and its true length, so this patch makes "len" unused. - For <prefix, prefix_len>, prefix could be a string that is longer than empty while prefix_len could be 0 when "--full-name" option is used. This is fixed by checking prefix_len in write_name() and calling write_name_quoted_relative() with NULL when prefix_len is set to 0. Again, this makes "prefix_len" given to write_name_quoted_relative() unused, without introducing a bug. Signed-off-by: Jiang Xin <worldhello.net@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-25 15:53:44 +00:00
name = relative_path(name, prefix, &sb);
write_name_quoted(name, fp, terminator);
strbuf_release(&sb);
}
/* quote path as relative to the given prefix */
char *quote_path_relative(const char *in, const char *prefix,
struct strbuf *out)
{
struct strbuf sb = STRBUF_INIT;
quote.c: substitute path_relative with relative_path Substitute the function path_relative in quote.c with the function relative_path. Function relative_path can be treated as an enhanced and more robust version of path_relative. Outputs of path_relative and it's replacement (relative_path) are the same for the following cases: path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/c/ /a/b/ c/ c/ /a/b/c /a/b/ c c /a/ /a/b/ ../ ../ / /a/b/ ../../ ../../ /a/c /a/b/ ../c ../c /x/y /a/b/ ../../x/y ../../x/y a/b/c/ a/b/ c/ c/ a/ a/b/ ../ ../ x/y a/b/ ../../x/y ../../x/y /a/b (empty) /a/b /a/b /a/b (null) /a/b /a/b a/b (empty) a/b a/b a/b (null) a/b a/b But if both of the path and the prefix are the same, or the returned relative path should be the current directory, the outputs of both functions are different. Function relative_path returns "./", while function path_relative returns empty string. path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/ /a/b/ (empty) ./ a/b/ a/b/ (empty) ./ (empty) (null) (empty) ./ (empty) (empty) (empty) ./ But the callers of path_relative can handle such cases, or never encounter this issue at all, because: * In function quote_path_relative, if the output of path_relative is empty, append "./" to it, like: if (!out->len) strbuf_addstr(out, "./"); * Another caller is write_name_quoted_relative, which is only used by builtin/ls-files.c. git-ls-files only show files, so path of files will never be identical with the prefix of a directory. The following differences show that path_relative does not handle extra slashes properly: path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a//b//c/ //a/b// ../../../../a//b//c/ c/ a/b//c a//b ../b//c c And if prefix has no trailing slash, path_relative does not work properly either. But since prefix always has a trailing slash, it's not a problem. path prefix output of path_relative output of relative_path ======== ========= ======================= ======================= /a/b/c/ /a/b b/c/ c/ /a/b /a/b b ./ /a/b/ /a/b b/ ./ /a /a/b/ ../../a ../ a/b/c/ a/b b/c/ c/ a/b/ a/b b/ ./ a a/b ../a ../ x/y a/b/ ../x/y ../../x/y a/c a/b c ../c /a/ /a/b (empty) ../ (empty) /a/b ../../ ./ One tricky part in this conversion is write_name() function in ls-files.c. It takes a counted string, <name, len>, that is to be made relative to <prefix, prefix_len> and then quoted. Because write_name_quoted_relative() still takes these two parameters as counted string, but ignores the count and treat these two as NUL-terminated strings, this conversion needs to be audited for its callers: - For <name, len>, all three callers of write_name() passes a NUL-terminated string and its true length, so this patch makes "len" unused. - For <prefix, prefix_len>, prefix could be a string that is longer than empty while prefix_len could be 0 when "--full-name" option is used. This is fixed by checking prefix_len in write_name() and calling write_name_quoted_relative() with NULL when prefix_len is set to 0. Again, this makes "prefix_len" given to write_name_quoted_relative() unused, without introducing a bug. Signed-off-by: Jiang Xin <worldhello.net@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-25 15:53:44 +00:00
const char *rel = relative_path(in, prefix, &sb);
strbuf_reset(out);
quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
strbuf_release(&sb);
return out->buf;
}
/*
* 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;
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_buf(struct strbuf *sb, const char *src)
{
const char sq = '\'';
const char bq = '\\';
char c;
strbuf_addch(sb, sq);
while ((c = *src++)) {
if (c == sq || c == bq)
strbuf_addch(sb, bq);
strbuf_addch(sb, c);
}
strbuf_addch(sb, sq);
}
void python_quote_buf(struct strbuf *sb, const char *src)
{
const char sq = '\'';
const char bq = '\\';
const char nl = '\n';
char c;
strbuf_addch(sb, sq);
while ((c = *src++)) {
if (c == nl) {
strbuf_addch(sb, bq);
strbuf_addch(sb, 'n');
continue;
}
if (c == sq || c == bq)
strbuf_addch(sb, bq);
strbuf_addch(sb, c);
}
strbuf_addch(sb, sq);
}
void tcl_quote_buf(struct strbuf *sb, const char *src)
{
char c;
strbuf_addch(sb, '"');
while ((c = *src++)) {
switch (c) {
case '[': case ']':
case '{': case '}':
case '$': case '\\': case '"':
strbuf_addch(sb, '\\');
default:
strbuf_addch(sb, c);
break;
case '\f':
strbuf_addstr(sb, "\\f");
break;
case '\r':
strbuf_addstr(sb, "\\r");
break;
case '\n':
strbuf_addstr(sb, "\\n");
break;
case '\t':
strbuf_addstr(sb, "\\t");
break;
case '\v':
strbuf_addstr(sb, "\\v");
break;
}
}
strbuf_addch(sb, '"');
}