Revert "Do not rely on pids being unique"

This reverts commit a07f46a3b0f7e452d50690b831bb4c99fbc6650f.

It turned out to be a bad idea to use mkstemp for temporary files that are
renamed into files to save in the cache since mkstemp creates the file with
permissions 0600.

diff --git a/ccache.c b/ccache.c
index 7b9fd0b0435b6dc5e46c90c22f61b3df420f3b7c..f0dca22c7fc76b76ba716c3268241b328c6de5ef 100644 (file)
--- a/ccache.c
+++ b/ccache.c
@@ -613,11 +613,8 @@ to_cache(struct args *args)
        unsigned added_files = 0;
 
        tmp_stdout = format("%s.tmp.stdout.%s", cached_obj, tmp_string());
-       create_empty_file(tmp_stdout);
        tmp_stderr = format("%s.tmp.stderr.%s", cached_obj, tmp_string());
-       create_empty_file(tmp_stderr);
        tmp_obj = format("%s.tmp.%s", cached_obj, tmp_string());
-       create_empty_file(tmp_obj);
 
        args_add(args, "-o");
        args_add(args, tmp_obj);
@@ -669,7 +666,7 @@ to_cache(struct args *args)
                int fd_result;
                char *tmp_stderr2;
 
-               tmp_stderr2 = format("%s.2", tmp_stderr);
+               tmp_stderr2 = format("%s.tmp.stderr2.%s", cached_obj, tmp_string());
                if (x_rename(tmp_stderr, tmp_stderr2)) {
                        cc_log("Failed to rename %s to %s: %s", tmp_stderr, tmp_stderr2,
                               strerror(errno));
@@ -811,21 +808,13 @@ get_object_name_from_cpp(struct args *args, struct mdfour *hash)
        }
 
        path_stderr = format("%s/tmp.cpp_stderr.%s", temp_dir, tmp_string());
-       create_empty_file(path_stderr);
        add_pending_tmp_file(path_stderr);
 
        time_of_compilation = time(NULL);
 
        if (!direct_i_file) {
-               /* The temporary file needs the proper i_extension for the compiler to do
-                * its thing. However, create_empty_file requires the tmp_string() part to
-                * be last, which is why the temporary file is created in two steps. */
-               char *path_stdout_tmp =
-                       format("%s/%s.tmp.%s", temp_dir, input_base, tmp_string());
-               create_empty_file(path_stdout_tmp);
-               path_stdout = format("%s.%s", path_stdout_tmp, i_extension);
-               x_rename(path_stdout_tmp, path_stdout);
-               free(path_stdout_tmp);
+               path_stdout = format("%s/%s.tmp.%s.%s",
+                                    temp_dir, input_base, tmp_string(), i_extension);
                add_pending_tmp_file(path_stdout);
 
                /* run cpp on the input file to obtain the .i */
@@ -838,6 +827,11 @@ get_object_name_from_cpp(struct args *args, struct mdfour *hash)
                   can skip the cpp stage and directly form the
                   correct i_tmpfile */
                path_stdout = input_file;
+               if (create_empty_file(path_stderr) != 0) {
+                       cc_log("Failed to create %s: %s", path_stderr, strerror(errno));
+                       stats_update(STATS_ERROR);
+                       failed();
+               }
                status = 0;
        }
 

diff --git a/ccache.h b/ccache.h
index adcc381609556f9f496b8f6e67fb190e21f622ef..ce4d1cf5779c749a2235c7be7677c0e90bdbba3a 100644 (file)
--- a/ccache.h
+++ b/ccache.h
@@ -133,7 +133,7 @@ size_t file_size(struct stat *st);
 int safe_open(const char *fname);
 char *x_realpath(const char *path);
 char *gnu_getcwd(void);
-int create_empty_file(char *fname);
+int create_empty_file(const char *fname);
 const char *get_home_directory(void);
 char *get_cwd();
 bool same_executable_name(const char *s1, const char *s2);

diff --git a/manifest.c b/manifest.c
index 660d437f6e515d1dec82eb235bee1f24dc018f74..7977418b0e3eee9c2d7f2504f7b485bdec014f01 100644 (file)
--- a/manifest.c
+++ b/manifest.c
@@ -653,7 +653,7 @@ manifest_put(const char *manifest_path, struct file_hash *object_hash,
        }
 
        tmp_file = format("%s.tmp.%s", manifest_path, tmp_string());
-       fd2 = mkstemp(tmp_file);
+       fd2 = safe_open(tmp_file);
        if (fd2 == -1) {
                cc_log("Failed to open %s", tmp_file);
                goto out;

diff --git a/stats.c b/stats.c
index 6a3c977e109e741e6af1fb3c9e293b3e174bf5a6..003a55450445b63d36c8a8c7cdfef4dbdd2d859f 100644 (file)
--- a/stats.c
+++ b/stats.c
@@ -126,15 +126,9 @@ stats_write(const char *path, struct counters *counters)
        size_t i;
        char *tmp_file;
        FILE *f;
-       int fd;
 
        tmp_file = format("%s.tmp.%s", path, tmp_string());
-       fd = mkstemp(tmp_file);
-       if (fd == -1) {
-               cc_log("Failed to open %s", tmp_file);
-               goto end;
-       }
-       f = fdopen(fd, "wb");
+       f = fopen(tmp_file, "wb");
        if (!f) {
                cc_log("Failed to open %s", tmp_file);
                goto end;
@@ -144,7 +138,7 @@ stats_write(const char *path, struct counters *counters)
                        fatal("Failed to write to %s", tmp_file);
                }
        }
-       fclose(f); /* This also implicitly closes the fd. */
+       fclose(f);
        x_rename(tmp_file, path);
 
 end:

diff --git a/util.c b/util.c
index 4c18e1576b20f78eab6c3f198e7cf7f191a3276e..ed470d2c3d376b1a46bf0eaafcf52f1f88039974 100644 (file)
--- a/util.c
+++ b/util.c
@@ -195,7 +195,7 @@ copy_file(const char *src, const char *dest, int compress_dest)
        struct stat st;
        int errnum;
 
-       tmp_name = format("%s.%s", dest, tmp_string());
+       tmp_name = format("%s.%s.XXXXXX", dest, tmp_string());
        cc_log("Copying %s to %s via %s (%s)",
               src, dest, tmp_name, compress_dest ? "compressed": "uncompressed");
 
@@ -418,8 +418,8 @@ get_hostname(void)
 }
 
 /*
- * Return a string to be passed to mkstemp to create a temporary file. Also
- * tries to cope with NFS by adding the local hostname.
+ * Return a string to be used to distinguish temporary files. Also tries to
+ * cope with NFS by adding the local hostname.
  */
 const char *
 tmp_string(void)
@@ -427,7 +427,7 @@ tmp_string(void)
        static char *ret;
 
        if (!ret) {
-               ret = format("%s.%u.XXXXXX", get_hostname(), (unsigned)getpid());
+               ret = format("%s.%u", get_hostname(), (unsigned)getpid());
        }
 
        return ret;
@@ -886,13 +886,12 @@ gnu_getcwd(void)
 
 /* create an empty file */
 int
-create_empty_file(char *fname)
+create_empty_file(const char *fname)
 {
        int fd;
 
-       fd = mkstemp(fname);
+       fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC|O_EXCL|O_BINARY, 0666);
        if (fd == -1) {
-               cc_log("Failed to create %s: %s", fname, strerror(errno));
                return -1;
        }
        close(fd);
@@ -1127,10 +1126,7 @@ x_unlink(const char *path)
                goto out;
        }
        if (unlink(tmp_name) == -1) {
-               /* If it was released in a race, that's OK. */
-               if (errno != ENOENT) {
-                       result = -1;
-               }
+               result = -1;
        }
 out:
        free(tmp_name);