[hackers] [scc] [driver] use random filenames for temporary object || Quentin Rameau

From: <git_AT_suckless.org>
Date: Mon, 18 Jul 2016 18:06:43 +0200 (CEST)

commit fe098f45fcb3847ae558bb7027c7701b6d2bc15f
Author: Quentin Rameau <quinq_AT_fifth.space>
AuthorDate: Thu Jun 30 17:21:46 2016 +0200
Commit: Quentin Rameau <quinq_AT_fifth.space>
CommitDate: Thu Jun 30 17:37:04 2016 +0200

    [driver] use random filenames for temporary object
    
    Those are generated in the form scc-XXXXXX and written in PWD or TMPDIR
    if it is set.

diff --git a/driver/posix/scc.c b/driver/posix/scc.c
index a68b796..a1cf9a8 100644
--- a/driver/posix/scc.c
+++ b/driver/posix/scc.c
_AT_@ -1,5 +1,6 @@
 /* See LICENSE file for copyright and license details. */
 #define _POSIX_SOURCE
+#define _XOPEN_SOURCE 500
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
_AT_@ -48,7 +49,9 @@ static struct tool {
 };
 
 char *argv0;
-static char *arch, *outfile;
+static char *arch, *objfile, *outfile;
+static char *tmpdir;
+static size_t tmpdirln;
 static struct items objtmp, objout;
 static int Eflag, Sflag, cflag, kflag, sflag;
 
_AT_@ -136,28 +139,31 @@ inittool(int tool)
 static char *
 outfilename(char *path, char *ext)
 {
- char *new, *name, *dot;
- size_t newsz, nameln;
- int n;
-
- if (!(name = strrchr(path, '/')))
- name = path;
- else
- ++name;
-
- nameln = strlen(name);
-
- if (!(dot = strrchr(name, '.')))
- dot = &name[nameln];
-
- nameln = nameln - strlen(dot);
- newsz = nameln + strlen(ext) + 1 + 1;
+ char *new, *fmt, *p;
+ size_t newsz, pathln;
+ int tmpfd, n;
+
+ if (path) {
+ fmt = "%.0s%.*4$s.%s";
+ if (p = strrchr(path, '/'))
+ path = p + 1;
+ pathln = strlen(path);
+ if (p = strrchr(path, '.'))
+ pathln -= strlen(p);
+ newsz = pathln + 1 + strlen(ext) + 1;
+ } else {
+ fmt = "%s/%s";
+ path = "scc-XXXXXX";
+ newsz = tmpdirln + 1 + strlen(path) + 1;
+ }
 
         new = xmalloc(newsz);
-
- n = snprintf(new, newsz, "%.*s.%s", nameln, name, ext);
+ n = snprintf(new, newsz, fmt, tmpdir, path, ext, pathln);
         if (n < 0 || n >= newsz)
                 die("scc: wrong output filename");
+ if ((tmpfd = mkstemp(new)) < 0 && errno != EINVAL)
+ die("scc: could not create output file");
+ close(tmpfd);
 
         return new;
 }
_AT_@ -184,8 +190,13 @@ settool(int tool, char *infile, int nexttool)
                 addarg(tool, t->outfile);
                 break;
         case AS:
- t->outfile = (cflag && outfile) ? outfile :
- outfilename(infile, "o");
+ if (cflag && outfile) {
+ objfile = outfile;
+ } else {
+ objfile = (cflag || kflag) ? infile : NULL;
+ objfile = outfilename(objfile, "o");
+ }
+ t->outfile = xstrdup(objfile);
                 addarg(tool, t->outfile);
                 break;
         case LD:
_AT_@ -290,6 +301,8 @@ validatetools(void)
                             !WIFEXITED(st) || WEXITSTATUS(st) != 0) {
                                 failure = 1;
                                 failed = tool;
+ free(objfile);
+ objfile = NULL;
                         }
                         if (tool >= failed && t->outfile)
                                 unlink(t->outfile);
_AT_@ -348,7 +361,7 @@ build(char *file)
         }
 
         if (validatetools())
- newitem(objs, outfilename(file, "o"));
+ newitem(objs, objfile);
 }
 
 static void
_AT_@ -433,6 +446,10 @@ main(int argc, char *argv[])
         if (Eflag && (Sflag || kflag) || argc > 1 && cflag && outfile || !argc)
                 usage();
 
+ if (!(tmpdir = getenv("TMPDIR")) || !tmpdir[0])
+ tmpdir = ".";
+ tmpdirln = strlen(tmpdir);
+
         for (; *argv; ++argv)
                 build(*argv);
 
Received on Mon Jul 18 2016 - 18:06:43 CEST