winegcc: Produce deterministic temporary file names

Add and use xorshift* pseudo random generator.
Replac mkstemps function with it.

Signed-off-by: Marko Semet <marko@marko10-000.de>

tools/winegcc/utils.c

@@ -384,3 +384,96 @@ int spawn(const strarray* prefix, const strarray* args, int ignore_errors)
     strarray_free(arr);
     return status;
 }
+
+/* xorshift* random generator. Source: https://en.wikipedia.org/wiki/Xorshift#xorshift* */
+static uint64_t pseudorandom_state = 1;
+extern char **environ;
+
+uint64_t pseudorandom(uint64_t add_to_state)
+{
+    uint64_t tmp = pseudorandom_state + add_to_state;
+    tmp ^= tmp >> 12;
+    tmp ^= tmp << 25;
+    tmp ^= tmp >> 27;
+    pseudorandom_state = tmp;
+    return tmp * UINT64_C(0x2545F4914F6CDD1D);
+}
+
+char pseudorandom_char(void)
+{
+    char tmp = (char) (pseudorandom(0) % 62);
+    if (tmp < 10)
+    {
+        return '0' + tmp;
+    }
+    else if (tmp < 36)
+    {
+        return 'A' + (tmp - 10);
+    }
+    else
+    {
+        return 'a' + (tmp - 36);
+    }
+}
+
+int pseudorandom_tempfile(char* file)
+{
+    /* replaces Xs */
+    for (char* tmp = file; (*tmp) != 0; tmp++)
+    {
+        if ((*tmp) == 'X')
+        {
+            (*tmp) = pseudorandom_char();
+        }
+    }
+
+    /* try to open file */
+    return open(file, O_CREAT | O_EXCL | O_RDWR, 0600);
+}
+
+void init_random_generator(int argc, char **argv)
+{
+    /* process environment */
+    {
+        /* copy environment variables and sort them */
+        char **tmp_envs;
+        unsigned int counter = 0;
+        for (const char **env = environ; (*env) != 0; env++, counter++) {}
+        tmp_envs = (char**) malloc(sizeof(char*) * counter);
+        for (unsigned int i = 0; i < counter; i++)
+        {
+            size_t length = strlen(environ[i]) + 1;
+            char* tmp = malloc(length);
+            memcpy(tmp, environ[i], length);
+            tmp_envs[i] = tmp;
+        }
+        qsort(tmp_envs, counter, sizeof(char*), (int(*)(const void*, const void*)) &strcmp);
+
+        /* add sorted environment to random generator */
+        for (unsigned int i = 0; i < counter; i++)
+        {
+            size_t j_max = strlen(tmp_envs[i]);
+            for (size_t j = 0; j < j_max; j++)
+            {
+                pseudorandom(tmp_envs[i][j]);
+            }
+        }
+
+        /* free temp environment */
+        for (unsigned int i = 0; i < counter; i++)
+        {
+            free(tmp_envs[i]);
+        }
+        free(tmp_envs);
+    }
+
+    /* process argv */
+    for (int i = 0; i < argc; i++)
+    {
+        size_t j_max = strlen(argv[i]);
+        for (size_t j = 0; j < j_max; j++)
+        {
+            pseudorandom(argv[i][j]);
+        }
+    }
+}

tools/winegcc/utils.h

@@ -25,6 +25,8 @@
 #define __attribute__(X)
 #endif
 
+#include <stdint.h>
+
 #ifndef DECLSPEC_NORETURN
 # if defined(_MSC_VER) && (_MSC_VER >= 1200) && !defined(MIDL_PASS)
 #  define DECLSPEC_NORETURN __declspec(noreturn)
@@ -90,3 +92,8 @@ const char *find_binary( const strarray* prefix, const char *name );
 int spawn(const strarray* prefix, const strarray* arr, int ignore_errors);
 
 extern int verbose;
+
+uint64_t pseudorandom(uint64_t add_to_state);
+char pseudorandom_char(void);
+int pseudorandom_tempfile(char* file);
+void init_random_generator(int argc, char **argv);

tools/winegcc/winegcc.c

@@ -299,7 +299,7 @@ static char* get_temp_file(const char* prefix, const char* suffix)
     /* block signals while manipulating the temp files list */
     sigprocmask( SIG_BLOCK, &signal_mask, &old_set );
 #endif
-    fd = mkstemps( tmp, strlen(suffix) );
+    fd = pseudorandom_tempfile(tmp);
     if (fd == -1)
     {
         /* could not create it in current directory, try in TMPDIR */
@@ -308,7 +308,7 @@ static char* get_temp_file(const char* prefix, const char* suffix)
         free(tmp);
         if (!(tmpdir = getenv("TMPDIR"))) tmpdir = "/tmp";
         tmp = strmake("%s/%s-XXXXXX%s", tmpdir, prefix, suffix);
-        fd = mkstemps( tmp, strlen(suffix) );
+        fd = pseudorandom_tempfile(tmp);
         if (fd == -1) error( "could not create temp file\n" );
     }
     close( fd );