https://github.com/git/git
Revision 9de0834663f28bee9e6b2c4647ed6128241ed26f authored by Linus Torvalds on 17 October 2006, 02:58:54 UTC, committed by Junio C Hamano on 17 October 2006, 04:27:44 UTC
Jim Mayering noticed that xdiff library took insanely long time when comparing files with many identical lines. This was because the hash function used in the library is broken on 64-bit architectures and caused too many collisions. http://thread.gmane.org/gmane.comp.version-control.git/28962/focus=28994 Acked-by: Davide Libenzi <davidel@xmaliserver.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
1 parent 6fe5b7f
Tip revision: 9de0834663f28bee9e6b2c4647ed6128241ed26f authored by Linus Torvalds on 17 October 2006, 02:58:54 UTC
Fix hash function in xdiff library
Fix hash function in xdiff library
Tip revision: 9de0834
ident.c
/*
* ident.c
*
* create git identifier lines of the form "name <email> date"
*
* Copyright (C) 2005 Linus Torvalds
*/
#include "cache.h"
#include <pwd.h>
#include <netdb.h>
static char git_default_date[50];
static void copy_gecos(struct passwd *w, char *name, int sz)
{
char *src, *dst;
int len, nlen;
nlen = strlen(w->pw_name);
/* Traditionally GECOS field had office phone numbers etc, separated
* with commas. Also & stands for capitalized form of the login name.
*/
for (len = 0, dst = name, src = w->pw_gecos; len < sz; src++) {
int ch = *src;
if (ch != '&') {
*dst++ = ch;
if (ch == 0 || ch == ',')
break;
len++;
continue;
}
if (len + nlen < sz) {
/* Sorry, Mr. McDonald... */
*dst++ = toupper(*w->pw_name);
memcpy(dst, w->pw_name + 1, nlen - 1);
dst += nlen - 1;
}
}
if (len < sz)
name[len] = 0;
else
die("Your parents must have hated you!");
}
int setup_ident(void)
{
int len;
struct passwd *pw = getpwuid(getuid());
if (!pw)
die("You don't exist. Go away!");
/* Get the name ("gecos") */
copy_gecos(pw, git_default_name, sizeof(git_default_name));
/* Make up a fake email address (name + '@' + hostname [+ '.' + domainname]) */
len = strlen(pw->pw_name);
if (len > sizeof(git_default_email)/2)
die("Your sysadmin must hate you!");
memcpy(git_default_email, pw->pw_name, len);
git_default_email[len++] = '@';
gethostname(git_default_email + len, sizeof(git_default_email) - len);
if (!strchr(git_default_email+len, '.')) {
struct hostent *he = gethostbyname(git_default_email + len);
char *domainname;
len = strlen(git_default_email);
git_default_email[len++] = '.';
if (he && (domainname = strchr(he->h_name, '.')))
strlcpy(git_default_email + len, domainname + 1, sizeof(git_default_email) - len);
else
strlcpy(git_default_email + len, "(none)", sizeof(git_default_email) - len);
}
/* And set the default date */
datestamp(git_default_date, sizeof(git_default_date));
return 0;
}
static int add_raw(char *buf, int size, int offset, const char *str)
{
int len = strlen(str);
if (offset + len > size)
return size;
memcpy(buf + offset, str, len);
return offset + len;
}
static int crud(unsigned char c)
{
static char crud_array[256];
static int crud_array_initialized = 0;
if (!crud_array_initialized) {
int k;
for (k = 0; k <= 31; ++k) crud_array[k] = 1;
crud_array[' '] = 1;
crud_array['.'] = 1;
crud_array[','] = 1;
crud_array[':'] = 1;
crud_array[';'] = 1;
crud_array['<'] = 1;
crud_array['>'] = 1;
crud_array['"'] = 1;
crud_array['\''] = 1;
crud_array_initialized = 1;
}
return crud_array[c];
}
/*
* Copy over a string to the destination, but avoid special
* characters ('\n', '<' and '>') and remove crud at the end
*/
static int copy(char *buf, int size, int offset, const char *src)
{
int i, len;
unsigned char c;
/* Remove crud from the beginning.. */
while ((c = *src) != 0) {
if (!crud(c))
break;
src++;
}
/* Remove crud from the end.. */
len = strlen(src);
while (len > 0) {
c = src[len-1];
if (!crud(c))
break;
--len;
}
/*
* Copy the rest to the buffer, but avoid the special
* characters '\n' '<' and '>' that act as delimiters on
* a identification line
*/
for (i = 0; i < len; i++) {
c = *src++;
switch (c) {
case '\n': case '<': case '>':
continue;
}
if (offset >= size)
return size;
buf[offset++] = c;
}
return offset;
}
static const char au_env[] = "GIT_AUTHOR_NAME";
static const char co_env[] = "GIT_COMMITTER_NAME";
static const char *env_hint =
"\n*** Environment problem:\n"
"*** Your name cannot be determined from your system services (gecos).\n"
"*** You would need to set %s and %s\n"
"*** environment variables; otherwise you won't be able to perform\n"
"*** certain operations because of \"empty ident\" errors.\n"
"*** Alternatively, you can use user.name configuration variable.\n\n";
static const char *get_ident(const char *name, const char *email,
const char *date_str, int error_on_no_name)
{
static char buffer[1000];
char date[50];
int i;
if (!name)
name = git_default_name;
if (!email)
email = git_default_email;
if (!*name) {
if (name == git_default_name && env_hint) {
fprintf(stderr, env_hint, au_env, co_env);
env_hint = NULL; /* warn only once, for "git-var -l" */
}
if (error_on_no_name)
die("empty ident %s <%s> not allowed", name, email);
}
strcpy(date, git_default_date);
if (date_str)
parse_date(date_str, date, sizeof(date));
i = copy(buffer, sizeof(buffer), 0, name);
i = add_raw(buffer, sizeof(buffer), i, " <");
i = copy(buffer, sizeof(buffer), i, email);
i = add_raw(buffer, sizeof(buffer), i, "> ");
i = copy(buffer, sizeof(buffer), i, date);
if (i >= sizeof(buffer))
die("Impossibly long personal identifier");
buffer[i] = 0;
return buffer;
}
const char *git_author_info(int error_on_no_name)
{
return get_ident(getenv("GIT_AUTHOR_NAME"),
getenv("GIT_AUTHOR_EMAIL"),
getenv("GIT_AUTHOR_DATE"),
error_on_no_name);
}
const char *git_committer_info(int error_on_no_name)
{
return get_ident(getenv("GIT_COMMITTER_NAME"),
getenv("GIT_COMMITTER_EMAIL"),
getenv("GIT_COMMITTER_DATE"),
error_on_no_name);
}
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