svn commit: r364166 - head/usr.sbin/crunch/crunchgen

[Rodney W. Grimes]

[ Charset UTF-8 unsupported, converting... ]
> Author: arichardson
> Date: Wed Aug 12 15:49:06 2020
> New Revision: 364166
> URL: https://svnweb.freebsd.org/changeset/base/364166
> 
> Log:
>   Fix crunchgen usage of mkstemp()
>   
>   On Glibc systems mkstemp can only be used once with the same template
>   string since it will be modified in-place and no longer contain any 'X' chars.
>   It is fine to reuse the same file here but we need to be explicit and use
>   open() instead of mkstemp() on the second use.
>   
>   While touching this file also avoid a hardcoded /bin/pwd since that may not
>   work when building on non-FreeBSD systems.

This may cause some grief, as now pwd may use a shell builtin
and often shell builtin's return a cwd that is not a true
full path, ie it may contain symlink compontents in the
path.

/bin/sh:

# cd /tmp/b
# /bin/pwd
/tmp/a
# pwd
/tmp/b
# ls -lag /tmp/?
lrwxr-xr-x  1 root  wheel  1 Aug 12 16:06 /tmp/b -> a

/tmp/a:
total 17
drwxr-xr-x   2 root  wheel    2 Aug 12 16:06 .
drwxrwxrwt  18 root  wheel  248 Aug 12 16:06 ..

>   
>   Reviewed By:	brooks
>   Differential Revision: https://reviews.freebsd.org/D25990
> 
> Modified:
>   head/usr.sbin/crunch/crunchgen/crunchgen.c
> 
> Modified: head/usr.sbin/crunch/crunchgen/crunchgen.c
> ==============================================================================
> --- head/usr.sbin/crunch/crunchgen/crunchgen.c	Wed Aug 12 14:45:31 2020	(r364165)
> +++ head/usr.sbin/crunch/crunchgen/crunchgen.c	Wed Aug 12 15:49:06 2020	(r364166)
> @@ -39,10 +39,13 @@ __FBSDID("$FreeBSD$");
>  
>  #include <ctype.h>
>  #include <err.h>
> +#include <fcntl.h>
>  #include <paths.h>
> +#include <stdbool.h>
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <string.h>
> +#include <sysexits.h>
>  #include <unistd.h>
>  
>  #define CRUNCH_VERSION	"0.2"
> @@ -91,6 +94,7 @@ prog_t   *progs     = NULL;
>  char confname[MAXPATHLEN], infilename[MAXPATHLEN];
>  char outmkname[MAXPATHLEN], outcfname[MAXPATHLEN], execfname[MAXPATHLEN];
>  char tempfname[MAXPATHLEN], cachename[MAXPATHLEN], curfilename[MAXPATHLEN];
> +bool tempfname_initialized = false;
>  char outhdrname[MAXPATHLEN] ;	/* user-supplied header for *.mk */
>  char *objprefix;		/* where are the objects ? */
>  char *path_make;
> @@ -216,6 +220,7 @@ main(int argc, char **argv)
>  	snprintf(cachename, sizeof(cachename), "%s.cache", confname);
>  	snprintf(tempfname, sizeof(tempfname), "%s/crunchgen_%sXXXXXX",
>  	getenv("TMPDIR") ? getenv("TMPDIR") : _PATH_TMP, confname);
> +	tempfname_initialized = false;
>  
>  	parse_conf_file();
>  	if (list_mode)
> @@ -648,8 +653,7 @@ fillin_program(prog_t *p)
>  
>  	/* Determine the actual srcdir (maybe symlinked). */
>  	if (p->srcdir) {
> -		snprintf(line, MAXLINELEN, "cd %s && echo -n `/bin/pwd`",
> -		    p->srcdir);
> +		snprintf(line, MAXLINELEN, "cd %s && pwd", p->srcdir);
>  		f = popen(line,"r");
>  		if (!f)
>  			errx(1, "Can't execute: %s\n", line);
> @@ -721,14 +725,26 @@ fillin_program_objs(prog_t *p, char *path)
>  
>  	/* discover the objs from the srcdir Makefile */
>  
> -	if ((fd = mkstemp(tempfname)) == -1) {
> -		perror(tempfname);
> -		exit(1);
> +	/*
> +	 * We reuse the same temporary file name for multiple objects. However,
> +	 * some libc implementations (such as glibc) return EINVAL if there
> +	 * are no XXXXX characters in the template. This happens after the
> +	 * first call to mkstemp since the argument is modified in-place.
> +	 * To avoid this error we use open() instead of mkstemp() after the
> +	 * call to mkstemp().
> +	 */
> +	if (tempfname_initialized) {
> +		if ((fd = open(tempfname, O_CREAT | O_EXCL | O_RDWR, 0600)) == -1) {
> +			err(EX_OSERR, "open(%s)", tempfname);
> +		}
> +	} else if ((fd = mkstemp(tempfname)) == -1) {
> +		err(EX_OSERR, "mkstemp(%s)", tempfname);
>  	}
> +	tempfname_initialized = true;
>  	if ((f = fdopen(fd, "w")) == NULL) {
> -		warn("%s", tempfname);
> +		warn("fdopen(%s)", tempfname);
>  		goterror = 1;
> -		return;
> +		goto out;
>  	}
>  	if (p->objvar)
>  		objvar = p->objvar;
> @@ -763,14 +779,14 @@ fillin_program_objs(prog_t *p, char *path)
>  	if ((f = popen(line, "r")) == NULL) {
>  		warn("submake pipe");
>  		goterror = 1;
> -		return;
> +		goto out;
>  	}
>  
>  	while(fgets(line, MAXLINELEN, f)) {
>  		if (strncmp(line, "OBJS= ", 6)) {
>  			warnx("make error: %s", line);
>  			goterror = 1;
> -			continue;
> +			goto out;
>  		}
>  
>  		cp = line + 6;
> @@ -793,7 +809,7 @@ fillin_program_objs(prog_t *p, char *path)
>  		warnx("make error: make returned %d", rc);
>  		goterror = 1;
>  	}
> -
> +out:
>  	unlink(tempfname);
>  }
>  
> 

-- 
Rod Grimes                                                 rgrimes at freebsd.org