git/ws.c
Elijah Newren 641223137b ws.h: move declarations for ws.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24 12:47:32 -07:00

389 lines
9.4 KiB
C

/*
* Whitespace rules
*
* Copyright (c) 2007 Junio C Hamano
*/
#include "git-compat-util.h"
#include "attr.h"
#include "strbuf.h"
#include "ws.h"
unsigned whitespace_rule_cfg = WS_DEFAULT_RULE;
static struct whitespace_rule {
const char *rule_name;
unsigned rule_bits;
unsigned loosens_error:1,
exclude_default:1;
} whitespace_rule_names[] = {
{ "trailing-space", WS_TRAILING_SPACE, 0 },
{ "space-before-tab", WS_SPACE_BEFORE_TAB, 0 },
{ "indent-with-non-tab", WS_INDENT_WITH_NON_TAB, 0 },
{ "cr-at-eol", WS_CR_AT_EOL, 1 },
{ "blank-at-eol", WS_BLANK_AT_EOL, 0 },
{ "blank-at-eof", WS_BLANK_AT_EOF, 0 },
{ "tab-in-indent", WS_TAB_IN_INDENT, 0, 1 },
};
unsigned parse_whitespace_rule(const char *string)
{
unsigned rule = WS_DEFAULT_RULE;
while (string) {
int i;
size_t len;
const char *ep;
const char *arg;
int negated = 0;
string = string + strspn(string, ", \t\n\r");
ep = strchrnul(string, ',');
len = ep - string;
if (*string == '-') {
negated = 1;
string++;
len--;
}
if (!len)
break;
for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++) {
if (strncmp(whitespace_rule_names[i].rule_name,
string, len))
continue;
if (negated)
rule &= ~whitespace_rule_names[i].rule_bits;
else
rule |= whitespace_rule_names[i].rule_bits;
break;
}
if (skip_prefix(string, "tabwidth=", &arg)) {
unsigned tabwidth = atoi(arg);
if (0 < tabwidth && tabwidth < 0100) {
rule &= ~WS_TAB_WIDTH_MASK;
rule |= tabwidth;
}
else
warning("tabwidth %.*s out of range",
(int)(ep - arg), arg);
}
string = ep;
}
if (rule & WS_TAB_IN_INDENT && rule & WS_INDENT_WITH_NON_TAB)
die("cannot enforce both tab-in-indent and indent-with-non-tab");
return rule;
}
unsigned whitespace_rule(struct index_state *istate, const char *pathname)
{
static struct attr_check *attr_whitespace_rule;
const char *value;
if (!attr_whitespace_rule)
attr_whitespace_rule = attr_check_initl("whitespace", NULL);
git_check_attr(istate, NULL, pathname, attr_whitespace_rule);
value = attr_whitespace_rule->items[0].value;
if (ATTR_TRUE(value)) {
/* true (whitespace) */
unsigned all_rule = ws_tab_width(whitespace_rule_cfg);
int i;
for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++)
if (!whitespace_rule_names[i].loosens_error &&
!whitespace_rule_names[i].exclude_default)
all_rule |= whitespace_rule_names[i].rule_bits;
return all_rule;
} else if (ATTR_FALSE(value)) {
/* false (-whitespace) */
return ws_tab_width(whitespace_rule_cfg);
} else if (ATTR_UNSET(value)) {
/* reset to default (!whitespace) */
return whitespace_rule_cfg;
} else {
/* string */
return parse_whitespace_rule(value);
}
}
/* The returned string should be freed by the caller. */
char *whitespace_error_string(unsigned ws)
{
struct strbuf err = STRBUF_INIT;
if ((ws & WS_TRAILING_SPACE) == WS_TRAILING_SPACE)
strbuf_addstr(&err, "trailing whitespace");
else {
if (ws & WS_BLANK_AT_EOL)
strbuf_addstr(&err, "trailing whitespace");
if (ws & WS_BLANK_AT_EOF) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "new blank line at EOF");
}
}
if (ws & WS_SPACE_BEFORE_TAB) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "space before tab in indent");
}
if (ws & WS_INDENT_WITH_NON_TAB) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "indent with spaces");
}
if (ws & WS_TAB_IN_INDENT) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "tab in indent");
}
return strbuf_detach(&err, NULL);
}
/* If stream is non-NULL, emits the line after checking. */
static unsigned ws_check_emit_1(const char *line, int len, unsigned ws_rule,
FILE *stream, const char *set,
const char *reset, const char *ws)
{
unsigned result = 0;
int written = 0;
int trailing_whitespace = -1;
int trailing_newline = 0;
int trailing_carriage_return = 0;
int i;
/* Logic is simpler if we temporarily ignore the trailing newline. */
if (len > 0 && line[len - 1] == '\n') {
trailing_newline = 1;
len--;
}
if ((ws_rule & WS_CR_AT_EOL) &&
len > 0 && line[len - 1] == '\r') {
trailing_carriage_return = 1;
len--;
}
/* Check for trailing whitespace. */
if (ws_rule & WS_BLANK_AT_EOL) {
for (i = len - 1; i >= 0; i--) {
if (isspace(line[i])) {
trailing_whitespace = i;
result |= WS_BLANK_AT_EOL;
}
else
break;
}
}
if (trailing_whitespace == -1)
trailing_whitespace = len;
/* Check indentation */
for (i = 0; i < trailing_whitespace; i++) {
if (line[i] == ' ')
continue;
if (line[i] != '\t')
break;
if ((ws_rule & WS_SPACE_BEFORE_TAB) && written < i) {
result |= WS_SPACE_BEFORE_TAB;
if (stream) {
fputs(ws, stream);
fwrite(line + written, i - written, 1, stream);
fputs(reset, stream);
fwrite(line + i, 1, 1, stream);
}
} else if (ws_rule & WS_TAB_IN_INDENT) {
result |= WS_TAB_IN_INDENT;
if (stream) {
fwrite(line + written, i - written, 1, stream);
fputs(ws, stream);
fwrite(line + i, 1, 1, stream);
fputs(reset, stream);
}
} else if (stream) {
fwrite(line + written, i - written + 1, 1, stream);
}
written = i + 1;
}
/* Check for indent using non-tab. */
if ((ws_rule & WS_INDENT_WITH_NON_TAB) && i - written >= ws_tab_width(ws_rule)) {
result |= WS_INDENT_WITH_NON_TAB;
if (stream) {
fputs(ws, stream);
fwrite(line + written, i - written, 1, stream);
fputs(reset, stream);
}
written = i;
}
if (stream) {
/*
* Now the rest of the line starts at "written".
* The non-highlighted part ends at "trailing_whitespace".
*/
/* Emit non-highlighted (middle) segment. */
if (trailing_whitespace - written > 0) {
fputs(set, stream);
fwrite(line + written,
trailing_whitespace - written, 1, stream);
fputs(reset, stream);
}
/* Highlight errors in trailing whitespace. */
if (trailing_whitespace != len) {
fputs(ws, stream);
fwrite(line + trailing_whitespace,
len - trailing_whitespace, 1, stream);
fputs(reset, stream);
}
if (trailing_carriage_return)
fputc('\r', stream);
if (trailing_newline)
fputc('\n', stream);
}
return result;
}
void ws_check_emit(const char *line, int len, unsigned ws_rule,
FILE *stream, const char *set,
const char *reset, const char *ws)
{
(void)ws_check_emit_1(line, len, ws_rule, stream, set, reset, ws);
}
unsigned ws_check(const char *line, int len, unsigned ws_rule)
{
return ws_check_emit_1(line, len, ws_rule, NULL, NULL, NULL, NULL);
}
int ws_blank_line(const char *line, int len)
{
/*
* We _might_ want to treat CR differently from other
* whitespace characters when ws_rule has WS_CR_AT_EOL, but
* for now we just use this stupid definition.
*/
while (len-- > 0) {
if (!isspace(*line))
return 0;
line++;
}
return 1;
}
/* Copy the line onto the end of the strbuf while fixing whitespaces */
void ws_fix_copy(struct strbuf *dst, const char *src, int len, unsigned ws_rule, int *error_count)
{
/*
* len is number of bytes to be copied from src, starting
* at src. Typically src[len-1] is '\n', unless this is
* the incomplete last line.
*/
int i;
int add_nl_to_tail = 0;
int add_cr_to_tail = 0;
int fixed = 0;
int last_tab_in_indent = -1;
int last_space_in_indent = -1;
int need_fix_leading_space = 0;
/*
* Strip trailing whitespace
*/
if (ws_rule & WS_BLANK_AT_EOL) {
if (0 < len && src[len - 1] == '\n') {
add_nl_to_tail = 1;
len--;
if (0 < len && src[len - 1] == '\r') {
add_cr_to_tail = !!(ws_rule & WS_CR_AT_EOL);
len--;
}
}
if (0 < len && isspace(src[len - 1])) {
while (0 < len && isspace(src[len-1]))
len--;
fixed = 1;
}
}
/*
* Check leading whitespaces (indent)
*/
for (i = 0; i < len; i++) {
char ch = src[i];
if (ch == '\t') {
last_tab_in_indent = i;
if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
0 <= last_space_in_indent)
need_fix_leading_space = 1;
} else if (ch == ' ') {
last_space_in_indent = i;
if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
ws_tab_width(ws_rule) <= i - last_tab_in_indent)
need_fix_leading_space = 1;
} else
break;
}
if (need_fix_leading_space) {
/* Process indent ourselves */
int consecutive_spaces = 0;
int last = last_tab_in_indent + 1;
if (ws_rule & WS_INDENT_WITH_NON_TAB) {
/* have "last" point at one past the indent */
if (last_tab_in_indent < last_space_in_indent)
last = last_space_in_indent + 1;
else
last = last_tab_in_indent + 1;
}
/*
* between src[0..last-1], strip the funny spaces,
* updating them to tab as needed.
*/
for (i = 0; i < last; i++) {
char ch = src[i];
if (ch != ' ') {
consecutive_spaces = 0;
strbuf_addch(dst, ch);
} else {
consecutive_spaces++;
if (consecutive_spaces == ws_tab_width(ws_rule)) {
strbuf_addch(dst, '\t');
consecutive_spaces = 0;
}
}
}
while (0 < consecutive_spaces--)
strbuf_addch(dst, ' ');
len -= last;
src += last;
fixed = 1;
} else if ((ws_rule & WS_TAB_IN_INDENT) && last_tab_in_indent >= 0) {
/* Expand tabs into spaces */
int start = dst->len;
int last = last_tab_in_indent + 1;
for (i = 0; i < last; i++) {
if (src[i] == '\t')
do {
strbuf_addch(dst, ' ');
} while ((dst->len - start) % ws_tab_width(ws_rule));
else
strbuf_addch(dst, src[i]);
}
len -= last;
src += last;
fixed = 1;
}
strbuf_add(dst, src, len);
if (add_cr_to_tail)
strbuf_addch(dst, '\r');
if (add_nl_to_tail)
strbuf_addch(dst, '\n');
if (fixed && error_count)
(*error_count)++;
}