qzdoom-gpl/tools/updaterevision/updaterevision.c
2016-03-01 09:47:10 -06:00

136 lines
2.9 KiB
C

/* updaterevision.c
*
* Public domain. This program uses git commands command to get
* various bits of repository status for a particular directory
* and writes it into a header file so that it can be used for a
* project's versioning.
*/
#define _CRT_SECURE_NO_DEPRECATE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#ifdef _WIN32
#define popen _popen
#define pclose _pclose
#endif
// Used to strip newline characters from lines read by fgets.
void stripnl(char *str)
{
if (*str != '\0')
{
size_t len = strlen(str);
if (str[len - 1] == '\n')
{
str[len - 1] = '\0';
}
}
}
int main(int argc, char **argv)
{
char vertag[128], lastlog[128], lasthash[128], *hash = NULL;
FILE *stream = NULL;
int gotrev = 0, needupdate = 1;
vertag[0] = '\0';
lastlog[0] = '\0';
if (argc != 2)
{
fprintf(stderr, "Usage: %s <path to gitinfo.h>\n", argv[0]);
return 1;
}
// Use git describe --tags to get a version string. If we are sitting directly
// on a tag, it returns that tag. Otherwise it returns <most recent tag>-<number of
// commits since the tag>-<short hash>.
// Use git log to get the time of the latest commit in ISO 8601 format and its full hash.
stream = popen("git describe --tags && git log -1 --format=%ai*%H", "r");
if (NULL != stream)
{
if (fgets(vertag, sizeof vertag, stream) == vertag &&
fgets(lastlog, sizeof lastlog, stream) == lastlog)
{
stripnl(vertag);
stripnl(lastlog);
gotrev = 1;
}
pclose(stream);
}
if (gotrev)
{
hash = strchr(lastlog, '*');
if (hash != NULL)
{
*hash = '\0';
hash++;
}
}
if (hash == NULL)
{
fprintf(stderr, "Failed to get commit info: %s\n", strerror(errno));
strcpy(vertag, "<unknown version>");
lastlog[0] = '\0';
lastlog[1] = '0';
lastlog[2] = '\0';
hash = lastlog + 1;
}
stream = fopen (argv[1], "r");
if (stream != NULL)
{
if (!gotrev)
{ // If we didn't get a revision but the file does exist, leave it alone.
fclose (stream);
return 0;
}
// Read the revision that's in this file already. If it's the same as
// what we've got, then we don't need to modify it and can avoid rebuilding
// dependant files.
if (fgets(lasthash, sizeof lasthash, stream) == lasthash)
{
stripnl(lasthash);
if (strcmp(hash, lasthash + 3) == 0)
{
needupdate = 0;
}
}
fclose (stream);
}
if (needupdate)
{
stream = fopen (argv[1], "w");
if (stream == NULL)
{
return 1;
}
fprintf(stream,
"// %s\n"
"//\n"
"// This file was automatically generated by the\n"
"// updaterevision tool. Do not edit by hand.\n"
"\n"
"#define GIT_DESCRIPTION \"%s\"\n"
"#define GIT_HASH \"%s\"\n"
"#define GIT_TIME \"%s\"\n",
hash, vertag, hash, lastlog);
fclose(stream);
fprintf(stderr, "%s updated to commit %s.\n", argv[1], vertag);
}
else
{
fprintf (stderr, "%s is up to date at commit %s.\n", argv[1], vertag);
}
return 0;
}