git/color.c
Jeff King 136c8c8b8f color: check color.ui in git_default_config()
Back in prehistoric times, our decision on whether or not to
show color by default relied on using a config callback that
either did or didn't load color config like color.diff.
When we introduced color.ui, we put it in the same boat:
commands had to manually respect it by using git_color_config()
or its git_color_default_config() convenience wrapper.

But in 4c7f1819b (make color.ui default to 'auto',
2013-06-10), that changed. Since then, we default color.ui
to auto in all programs, meaning that even plumbing commands
like "git diff-tree --pretty" might colorize the output.
Nobody seems to have complained in the intervening years,
presumably because the "is stdout a tty" check does a good
job of catching the right cases.

But that leaves an interesting curiosity: color.ui defaults
to auto even in plumbing, but you can't actually _disable_
the color via config. So if you really hate color and set
"color.ui" to false, diff-tree will still show color (but
porcelain like git-diff won't).  Nobody noticed that either,
probably because very few people disable color.

One could argue that the plumbing should _always_ disable
color unless an explicit --color option is given on the
command line. But in practice, this creates a lot of
complications for scripts which do want plumbing to show
user-visible output. They can't just pass "--color" blindly;
they need to check the user's config and decide what to
send.

Given that nobody has complained about the current behavior,
let's assume it's a good path, and follow it to its
conclusion: supporting color.ui everywhere.

Note that you can create havoc by setting color.ui=always in
your config, but that's more or less already the case. We
could disallow it entirely, but it is handy for one-offs
like:

  git -c color.ui=always foo >not-a-tty

when "foo" does not take a --color option itself.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-13 12:42:51 -07:00

414 lines
8.3 KiB
C

#include "cache.h"
#include "config.h"
#include "color.h"
static int git_use_color_default = GIT_COLOR_AUTO;
int color_stdout_is_tty = -1;
/*
* The list of available column colors.
*/
const char *column_colors_ansi[] = {
GIT_COLOR_RED,
GIT_COLOR_GREEN,
GIT_COLOR_YELLOW,
GIT_COLOR_BLUE,
GIT_COLOR_MAGENTA,
GIT_COLOR_CYAN,
GIT_COLOR_BOLD_RED,
GIT_COLOR_BOLD_GREEN,
GIT_COLOR_BOLD_YELLOW,
GIT_COLOR_BOLD_BLUE,
GIT_COLOR_BOLD_MAGENTA,
GIT_COLOR_BOLD_CYAN,
GIT_COLOR_RESET,
};
/* Ignore the RESET at the end when giving the size */
const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
/* An individual foreground or background color. */
struct color {
enum {
COLOR_UNSPECIFIED = 0,
COLOR_NORMAL,
COLOR_ANSI, /* basic 0-7 ANSI colors */
COLOR_256,
COLOR_RGB
} type;
/* The numeric value for ANSI and 256-color modes */
unsigned char value;
/* 24-bit RGB color values */
unsigned char red, green, blue;
};
/*
* "word" is a buffer of length "len"; does it match the NUL-terminated
* "match" exactly?
*/
static int match_word(const char *word, int len, const char *match)
{
return !strncasecmp(word, match, len) && !match[len];
}
static int get_hex_color(const char *in, unsigned char *out)
{
unsigned int val;
val = (hexval(in[0]) << 4) | hexval(in[1]);
if (val & ~0xff)
return -1;
*out = val;
return 0;
}
static int parse_color(struct color *out, const char *name, int len)
{
/* Positions in array must match ANSI color codes */
static const char * const color_names[] = {
"black", "red", "green", "yellow",
"blue", "magenta", "cyan", "white"
};
char *end;
int i;
long val;
/* First try the special word "normal"... */
if (match_word(name, len, "normal")) {
out->type = COLOR_NORMAL;
return 0;
}
/* Try a 24-bit RGB value */
if (len == 7 && name[0] == '#') {
if (!get_hex_color(name + 1, &out->red) &&
!get_hex_color(name + 3, &out->green) &&
!get_hex_color(name + 5, &out->blue)) {
out->type = COLOR_RGB;
return 0;
}
}
/* Then pick from our human-readable color names... */
for (i = 0; i < ARRAY_SIZE(color_names); i++) {
if (match_word(name, len, color_names[i])) {
out->type = COLOR_ANSI;
out->value = i;
return 0;
}
}
/* And finally try a literal 256-color-mode number */
val = strtol(name, &end, 10);
if (end - name == len) {
/*
* Allow "-1" as an alias for "normal", but other negative
* numbers are bogus.
*/
if (val < -1)
; /* fall through to error */
else if (val < 0) {
out->type = COLOR_NORMAL;
return 0;
/* Rewrite low numbers as more-portable standard colors. */
} else if (val < 8) {
out->type = COLOR_ANSI;
out->value = val;
return 0;
} else if (val < 256) {
out->type = COLOR_256;
out->value = val;
return 0;
}
}
return -1;
}
static int parse_attr(const char *name, size_t len)
{
static const struct {
const char *name;
size_t len;
int val, neg;
} attrs[] = {
#define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
ATTR("bold", 1, 22),
ATTR("dim", 2, 22),
ATTR("italic", 3, 23),
ATTR("ul", 4, 24),
ATTR("blink", 5, 25),
ATTR("reverse", 7, 27),
ATTR("strike", 9, 29)
#undef ATTR
};
int negate = 0;
int i;
if (skip_prefix_mem(name, len, "no", &name, &len)) {
skip_prefix_mem(name, len, "-", &name, &len);
negate = 1;
}
for (i = 0; i < ARRAY_SIZE(attrs); i++) {
if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
return negate ? attrs[i].neg : attrs[i].val;
}
return -1;
}
int color_parse(const char *value, char *dst)
{
return color_parse_mem(value, strlen(value), dst);
}
void color_set(char *dst, const char *color_bytes)
{
xsnprintf(dst, COLOR_MAXLEN, "%s", color_bytes);
}
/*
* Write the ANSI color codes for "c" to "out"; the string should
* already have the ANSI escape code in it. "out" should have enough
* space in it to fit any color.
*/
static char *color_output(char *out, int len, const struct color *c, char type)
{
switch (c->type) {
case COLOR_UNSPECIFIED:
case COLOR_NORMAL:
break;
case COLOR_ANSI:
if (len < 2)
die("BUG: color parsing ran out of space");
*out++ = type;
*out++ = '0' + c->value;
break;
case COLOR_256:
out += xsnprintf(out, len, "%c8;5;%d", type, c->value);
break;
case COLOR_RGB:
out += xsnprintf(out, len, "%c8;2;%d;%d;%d", type,
c->red, c->green, c->blue);
break;
}
return out;
}
static int color_empty(const struct color *c)
{
return c->type <= COLOR_NORMAL;
}
int color_parse_mem(const char *value, int value_len, char *dst)
{
const char *ptr = value;
int len = value_len;
char *end = dst + COLOR_MAXLEN;
unsigned int attr = 0;
struct color fg = { COLOR_UNSPECIFIED };
struct color bg = { COLOR_UNSPECIFIED };
while (len > 0 && isspace(*ptr)) {
ptr++;
len--;
}
if (!len) {
dst[0] = '\0';
return 0;
}
if (!strncasecmp(ptr, "reset", len)) {
xsnprintf(dst, end - dst, GIT_COLOR_RESET);
return 0;
}
/* [fg [bg]] [attr]... */
while (len > 0) {
const char *word = ptr;
struct color c = { COLOR_UNSPECIFIED };
int val, wordlen = 0;
while (len > 0 && !isspace(word[wordlen])) {
wordlen++;
len--;
}
ptr = word + wordlen;
while (len > 0 && isspace(*ptr)) {
ptr++;
len--;
}
if (!parse_color(&c, word, wordlen)) {
if (fg.type == COLOR_UNSPECIFIED) {
fg = c;
continue;
}
if (bg.type == COLOR_UNSPECIFIED) {
bg = c;
continue;
}
goto bad;
}
val = parse_attr(word, wordlen);
if (0 <= val)
attr |= (1 << val);
else
goto bad;
}
#undef OUT
#define OUT(x) do { \
if (dst == end) \
die("BUG: color parsing ran out of space"); \
*dst++ = (x); \
} while(0)
if (attr || !color_empty(&fg) || !color_empty(&bg)) {
int sep = 0;
int i;
OUT('\033');
OUT('[');
for (i = 0; attr; i++) {
unsigned bit = (1 << i);
if (!(attr & bit))
continue;
attr &= ~bit;
if (sep++)
OUT(';');
dst += xsnprintf(dst, end - dst, "%d", i);
}
if (!color_empty(&fg)) {
if (sep++)
OUT(';');
/* foreground colors are all in the 3x range */
dst = color_output(dst, end - dst, &fg, '3');
}
if (!color_empty(&bg)) {
if (sep++)
OUT(';');
/* background colors are all in the 4x range */
dst = color_output(dst, end - dst, &bg, '4');
}
OUT('m');
}
OUT(0);
return 0;
bad:
return error(_("invalid color value: %.*s"), value_len, value);
#undef OUT
}
int git_config_colorbool(const char *var, const char *value)
{
if (value) {
if (!strcasecmp(value, "never"))
return 0;
if (!strcasecmp(value, "always"))
return 1;
if (!strcasecmp(value, "auto"))
return GIT_COLOR_AUTO;
}
if (!var)
return -1;
/* Missing or explicit false to turn off colorization */
if (!git_config_bool(var, value))
return 0;
/* any normal truth value defaults to 'auto' */
return GIT_COLOR_AUTO;
}
static int check_auto_color(void)
{
if (color_stdout_is_tty < 0)
color_stdout_is_tty = isatty(1);
if (color_stdout_is_tty || (pager_in_use() && pager_use_color)) {
char *term = getenv("TERM");
if (term && strcmp(term, "dumb"))
return 1;
}
return 0;
}
int want_color(int var)
{
static int want_auto = -1;
if (var < 0)
var = git_use_color_default;
if (var == GIT_COLOR_AUTO) {
if (want_auto < 0)
want_auto = check_auto_color();
return want_auto;
}
return var;
}
int git_color_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "color.ui")) {
git_use_color_default = git_config_colorbool(var, value);
return 0;
}
return 0;
}
void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
{
if (*color)
fprintf(fp, "%s", color);
fprintf(fp, "%s", sb->buf);
if (*color)
fprintf(fp, "%s", GIT_COLOR_RESET);
}
static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
va_list args, const char *trail)
{
int r = 0;
if (*color)
r += fprintf(fp, "%s", color);
r += vfprintf(fp, fmt, args);
if (*color)
r += fprintf(fp, "%s", GIT_COLOR_RESET);
if (trail)
r += fprintf(fp, "%s", trail);
return r;
}
int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
{
va_list args;
int r;
va_start(args, fmt);
r = color_vfprintf(fp, color, fmt, args, NULL);
va_end(args);
return r;
}
int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
{
va_list args;
int r;
va_start(args, fmt);
r = color_vfprintf(fp, color, fmt, args, "\n");
va_end(args);
return r;
}
int color_is_nil(const char *c)
{
return !strcmp(c, "NIL");
}