Revision 24ff4d56cf400126aa93ac9a5b9d8a21afadf3f6 authored by Björn Gustavsson on 06 March 2010, 14:30:29 UTC, committed by Junio C Hamano on 07 March 2010, 07:53:00 UTC
In the next commit, we will make it possible for blank context
lines to match beyond the end of the file. That means that a hunk
with a preimage that has more lines than present in the file may
be possible to successfully apply. Therefore, we must remove
the quick rejection test in find_pos().

find_pos() will already work correctly without the quick
rejection test, but that might not be obvious. Therefore,
comment the test for handling out-of-range line numbers in
find_pos() and cast the "line" variable to the same (unsigned)
type as img->nr.

What are performance implications of removing the quick
rejection test?

It can only help "git apply" to reject a patch faster. For example,
if I have a file with one million lines and a patch that removes
slightly more than 50 percent of the lines and try to apply that
patch twice, the second attempt will fail slightly faster
with the test than without (based on actual measurements).

However, there is the pathological case of a patch with many
more context lines than the default three, and applying that patch
using "git apply -C1". Without the rejection test, the running
time will be roughly proportional to the number of context lines
times the size of the file. That could be handled by writing
a more complicated rejection test (it would have to count the
number of blanks at the end of the preimage), but I don't find
that worth doing until there is a real-world use case that
would benfit from it.

It would be possible to keep the quick rejection test if
--whitespace=fix is not given, but I don't like that from
a testing point of view.

Signed-off-by: Björn Gustavsson <bgustavsson@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 9b25949
Raw File
color.c
#include "cache.h"
#include "color.h"

int git_use_color_default = 0;

static int parse_color(const char *name, int len)
{
	static const char * const color_names[] = {
		"normal", "black", "red", "green", "yellow",
		"blue", "magenta", "cyan", "white"
	};
	char *end;
	int i;
	for (i = 0; i < ARRAY_SIZE(color_names); i++) {
		const char *str = color_names[i];
		if (!strncasecmp(name, str, len) && !str[len])
			return i - 1;
	}
	i = strtol(name, &end, 10);
	if (end - name == len && i >= -1 && i <= 255)
		return i;
	return -2;
}

static int parse_attr(const char *name, int len)
{
	static const int attr_values[] = { 1, 2, 4, 5, 7 };
	static const char * const attr_names[] = {
		"bold", "dim", "ul", "blink", "reverse"
	};
	int i;
	for (i = 0; i < ARRAY_SIZE(attr_names); i++) {
		const char *str = attr_names[i];
		if (!strncasecmp(name, str, len) && !str[len])
			return attr_values[i];
	}
	return -1;
}

void color_parse(const char *value, const char *var, char *dst)
{
	color_parse_mem(value, strlen(value), var, dst);
}

void color_parse_mem(const char *value, int value_len, const char *var,
		char *dst)
{
	const char *ptr = value;
	int len = value_len;
	int attr = -1;
	int fg = -2;
	int bg = -2;

	if (!strncasecmp(value, "reset", len)) {
		strcpy(dst, GIT_COLOR_RESET);
		return;
	}

	/* [fg [bg]] [attr] */
	while (len > 0) {
		const char *word = ptr;
		int val, wordlen = 0;

		while (len > 0 && !isspace(word[wordlen])) {
			wordlen++;
			len--;
		}

		ptr = word + wordlen;
		while (len > 0 && isspace(*ptr)) {
			ptr++;
			len--;
		}

		val = parse_color(word, wordlen);
		if (val >= -1) {
			if (fg == -2) {
				fg = val;
				continue;
			}
			if (bg == -2) {
				bg = val;
				continue;
			}
			goto bad;
		}
		val = parse_attr(word, wordlen);
		if (val < 0 || attr != -1)
			goto bad;
		attr = val;
	}

	if (attr >= 0 || fg >= 0 || bg >= 0) {
		int sep = 0;

		*dst++ = '\033';
		*dst++ = '[';
		if (attr >= 0) {
			*dst++ = '0' + attr;
			sep++;
		}
		if (fg >= 0) {
			if (sep++)
				*dst++ = ';';
			if (fg < 8) {
				*dst++ = '3';
				*dst++ = '0' + fg;
			} else {
				dst += sprintf(dst, "38;5;%d", fg);
			}
		}
		if (bg >= 0) {
			if (sep++)
				*dst++ = ';';
			if (bg < 8) {
				*dst++ = '4';
				*dst++ = '0' + bg;
			} else {
				dst += sprintf(dst, "48;5;%d", bg);
			}
		}
		*dst++ = 'm';
	}
	*dst = 0;
	return;
bad:
	die("bad color value '%.*s' for variable '%s'", value_len, value, var);
}

int git_config_colorbool(const char *var, const char *value, int stdout_is_tty)
{
	if (value) {
		if (!strcasecmp(value, "never"))
			return 0;
		if (!strcasecmp(value, "always"))
			return 1;
		if (!strcasecmp(value, "auto"))
			goto auto_color;
	}

	/* Missing or explicit false to turn off colorization */
	if (!git_config_bool(var, value))
		return 0;

	/* any normal truth value defaults to 'auto' */
 auto_color:
	if (stdout_is_tty < 0)
		stdout_is_tty = isatty(1);
	if (stdout_is_tty || (pager_in_use() && pager_use_color)) {
		char *term = getenv("TERM");
		if (term && strcmp(term, "dumb"))
			return 1;
	}
	return 0;
}

int git_color_default_config(const char *var, const char *value, void *cb)
{
	if (!strcmp(var, "color.ui")) {
		git_use_color_default = git_config_colorbool(var, value, -1);
		return 0;
	}

	return git_default_config(var, value, cb);
}

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;
}

/*
 * This function splits the buffer by newlines and colors the lines individually.
 *
 * Returns 0 on success.
 */
int color_fwrite_lines(FILE *fp, const char *color,
		size_t count, const char *buf)
{
	if (!*color)
		return fwrite(buf, count, 1, fp) != 1;
	while (count) {
		char *p = memchr(buf, '\n', count);
		if (p != buf && (fputs(color, fp) < 0 ||
				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
				fputs(GIT_COLOR_RESET, fp) < 0))
			return -1;
		if (!p)
			return 0;
		if (fputc('\n', fp) < 0)
			return -1;
		count -= p + 1 - buf;
		buf = p + 1;
	}
	return 0;
}


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