git-commit-vandalism/color.c
Jeff King 55cccf4bb3 color_parse_mem: allow empty color spec
Prior to c2f41bf52 (color.c: fix color_parse_mem() with
value_len == 0, 2017-01-19), the empty string was
interpreted as a color "reset". This was an accidental
outcome, and that commit turned it into an error.

However, scripts may pass the empty string as a default
value to "git config --get-color" to disable color when the
value is not defined. The git-add--interactive script does
this. As a result, the script is unusable since c2f41bf52
unless you have color.diff.plain defined (if it is defined,
then we don't parse the empty default at all).

Our test scripts didn't notice the recent breakage because
they run without a terminal, and thus without color. They
never hit this code path at all. And nobody noticed the
original buggy "reset" behavior, because it was effectively
a noop.

Let's fix the code to have an empty color name produce an
empty sequence of color codes. The tests need a few fixups:

  - we'll add a new test in t4026 to cover this case. But
    note that we need to tweak the color() helper. While
    we're there, let's factor out the literal ANSI ESC
    character. Otherwise it makes the diff quite hard to
    read.

  - we'll add a basic sanity-check in t4026 that "git add
    -p" works at all when color is enabled. That would have
    caught this bug, as well as any others that are specific
    to the color code paths.

  - 73c727d69 (log --graph: customize the graph lines with
    config log.graphColors, 2017-01-19) added a test to
    t4202 that checks some "invalid" graph color config.
    Since ",, blue" before yielded only "blue" as valid, and
    now yields "empty, empty, blue", we don't match the
    expected output.

    One way to fix this would be to change the expectation
    to the empty color strings. But that makes the test much
    less interesting, since we show only two graph lines,
    both of which would be colorless.

    Since the empty-string case is now covered by t4026,
    let's remove them entirely here. They're just in the way
    of the primary thing the test is supposed to be
    checking.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-31 21:02:04 -08:00

421 lines
8.5 KiB
C

#include "cache.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;
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;
}
int git_color_default_config(const char *var, const char *value, void *cb)
{
if (git_color_config(var, value, cb) < 0)
return -1;
return git_default_config(var, value, cb);
}
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");
}