git/quote.c
Calvin Wan 91c080dff5 git-compat-util: move alloc macros to git-compat-util.h
alloc_nr, ALLOC_GROW, and ALLOC_GROW_BY are commonly used macros for
dynamic array allocation. Moving these macros to git-compat-util.h with
the other alloc macros focuses alloc.[ch] to allocation for Git objects
and additionally allows us to remove inclusions to alloc.h from files
that solely used the above macros.

Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-07-05 11:42:31 -07:00

585 lines
12 KiB
C

#include "git-compat-util.h"
#include "path.h"
#include "quote.h"
#include "strbuf.h"
#include "strvec.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_quote_buf_pretty(struct strbuf *dst, const char *src)
{
static const char ok_punct[] = "+,-./:=@_^";
const char *p;
/* Avoid losing a zero-length string by adding '' */
if (!*src) {
strbuf_addstr(dst, "''");
return;
}
for (p = src; *p; p++) {
if (!isalnum(*p) && !strchr(ok_punct, *p)) {
sq_quote_buf(dst, src);
return;
}
}
/* if we get here, we did not need quoting */
strbuf_addstr(dst, src);
}
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)
{
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]);
}
}
/*
* Legacy function to append each argv value, quoted as necessasry,
* with whitespace before each value. This results in a leading
* space in the result.
*/
void sq_quote_argv_pretty(struct strbuf *dst, const char **argv)
{
if (argv[0])
strbuf_addch(dst, ' ');
sq_append_quote_argv_pretty(dst, argv);
}
/*
* Append each argv value, quoted as necessary, with whitespace between them.
*/
void sq_append_quote_argv_pretty(struct strbuf *dst, const char **argv)
{
int i;
for (i = 0; argv[i]; i++) {
if (i > 0)
strbuf_addch(dst, ' ');
sq_quote_buf_pretty(dst, argv[i]);
}
}
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 '\\':
/*
* Allow backslashed characters outside of
* single-quotes only if they need escaping,
* and only if we resume the single-quoted part
* afterward.
*/
if (need_bs_quote(src[1]) && src[2] == '\'') {
*dst++ = src[1];
src += 2;
continue;
}
/* Fallthrough */
default:
if (!next)
return NULL;
*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 strvec *array)
{
char *next = arg;
if (!*arg)
return 0;
do {
char *dequoted = sq_dequote_step(next, &next);
if (!dequoted)
return -1;
if (next) {
char c;
if (!isspace(*next))
return -1;
do {
c = *++next;
} while (isspace(c));
}
if (argv) {
ALLOC_GROW(*argv, *nr + 1, *alloc);
(*argv)[(*nr)++] = dequoted;
}
if (array)
strvec_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_strvec(char *arg, struct strvec *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 cq_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 cq_must_quote(char c)
{
return cq_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; !cq_must_quote(s[len]); len++);
} else {
for (len = 0; len < maxlen && !cq_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, unsigned flags)
{
#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)
int no_dq = !!(flags & CQUOTE_NODQ);
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 (cq_lookup[ch] >= ' ') {
EMIT(cq_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, unsigned flags)
{
return quote_c_style_counted(name, -1, sb, fp, flags);
}
void quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path,
unsigned flags)
{
int nodq = !!(flags & CQUOTE_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, CQUOTE_NODQ);
quote_c_style(path, sb, NULL, CQUOTE_NODQ);
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;
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(const char *in, const char *prefix, struct strbuf *out, unsigned flags)
{
struct strbuf sb = STRBUF_INIT;
const char *rel = relative_path(in, prefix, &sb);
int force_dq = ((flags & QUOTE_PATH_QUOTE_SP) && strchr(rel, ' '));
strbuf_reset(out);
/*
* If the caller wants us to enclose the output in a dq-pair
* whether quote_c_style_counted() needs to, we do it ourselves
* and tell quote_c_style_counted() not to.
*/
if (force_dq)
strbuf_addch(out, '"');
quote_c_style_counted(rel, strlen(rel), out, NULL,
force_dq ? CQUOTE_NODQ : 0);
if (force_dq)
strbuf_addch(out, '"');
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 perl_quote_buf_with_len(struct strbuf *sb, const char *src, size_t len)
{
const char sq = '\'';
const char bq = '\\';
const char *c = src;
const char *end = src + len;
strbuf_addch(sb, sq);
while (c != end) {
if (*c == sq || *c == bq)
strbuf_addch(sb, bq);
strbuf_addch(sb, *c);
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 '$': case '\\': case '"':
strbuf_addch(sb, '\\');
/* fallthrough */
default:
strbuf_addch(sb, c);
break;
case '\f':
strbuf_addstr(sb, "\\f");
break;
case '\r':
strbuf_addstr(sb, "\\r");
break;
case '\n':
strbuf_addstr(sb, "\\n");
break;
case '\t':
strbuf_addstr(sb, "\\t");
break;
case '\v':
strbuf_addstr(sb, "\\v");
break;
}
}
strbuf_addch(sb, '"');
}
void basic_regex_quote_buf(struct strbuf *sb, const char *src)
{
char c;
if (*src == '^') {
/* only beginning '^' is special and needs quoting */
strbuf_addch(sb, '\\');
strbuf_addch(sb, *src++);
}
if (*src == '*')
/* beginning '*' is not special, no quoting */
strbuf_addch(sb, *src++);
while ((c = *src++)) {
switch (c) {
case '[':
case '.':
case '\\':
case '*':
strbuf_addch(sb, '\\');
strbuf_addch(sb, c);
break;
case '$':
/* only the end '$' is special and needs quoting */
if (*src == '\0')
strbuf_addch(sb, '\\');
strbuf_addch(sb, c);
break;
default:
strbuf_addch(sb, c);
break;
}
}
}