Refactor the code that counts the last log version to keep

When silencing the Coverity warning in remove_old_tsversions(), the code
was refactored to reduce the indentation levels and break down the long
code into individual functions.  This improve fix for [GL #1989].

diff --git a/lib/isc/log.c b/lib/isc/log.c
index dc605d3e8dc62398489224b5b44549ab6038cfb4..8bbdcea19e5076a4616431b177fa117acf7fdbbb 100644 (file)
--- a/lib/isc/log.c
+++ b/lib/isc/log.c
@@ -1102,13 +1102,67 @@ greatest_version(isc_logfile_t *file, int versions, int *greatestp) {
        return (ISC_R_SUCCESS);
 }
 
+static void
+insert_sort(int64_t to_keep[], int64_t versions, int version) {
+       int i = 0;
+       while (i < versions && version < to_keep[i]) {
+               i++;
+       }
+       if (i == versions) {
+               return;
+       }
+       if (i < versions - 1) {
+               memmove(&to_keep[i + 1], &to_keep[i],
+                       sizeof(to_keep[0]) * (versions - i - 1));
+       }
+       to_keep[i] = version;
+}
+
+static int64_t
+last_to_keep(int64_t versions, isc_dir_t *dirp, char *bname, size_t bnamelen) {
+       if (versions <= 0) {
+               return INT64_MAX;
+       }
+
+       int64_t to_keep[ISC_LOG_MAX_VERSIONS] = { 0 };
+       int64_t version = 0;
+       if (versions > ISC_LOG_MAX_VERSIONS) {
+               versions = ISC_LOG_MAX_VERSIONS;
+       }
+       /*
+        * First we fill 'to_keep' structure using insertion sort
+        */
+       memset(to_keep, 0, sizeof(to_keep));
+       while (isc_dir_read(dirp) == ISC_R_SUCCESS) {
+               if (dirp->entry.length <= bnamelen ||
+                   strncmp(dirp->entry.name, bname, bnamelen) != 0 ||
+                   dirp->entry.name[bnamelen] != '.')
+               {
+                       continue;
+               }
+
+               char *digit_end;
+               char *ename = &dirp->entry.name[bnamelen + 1];
+               version = strtoull(ename, &digit_end, 10);
+               if (*digit_end == '\0') {
+                       insert_sort(to_keep, versions, version);
+               }
+       }
+
+       isc_dir_reset(dirp);
+
+       /*
+        * to_keep[versions - 1] is the last one we want to keep
+        */
+       return (to_keep[versions - 1]);
+}
+
 static isc_result_t
 remove_old_tsversions(isc_logfile_t *file, int versions) {
        isc_result_t result;
        char *bname, *digit_end;
        const char *dirname;
        int64_t version, last = INT64_MAX;
-       int64_t to_keep[ISC_LOG_MAX_VERSIONS];
        size_t bnamelen;
        isc_dir_t dir;
        char sep = '/';
@@ -1155,45 +1209,7 @@ remove_old_tsversions(isc_logfile_t *file, int versions) {
                return (result);
        }
 
-       if (versions > 0) {
-               if (versions > ISC_LOG_MAX_VERSIONS) {
-                       versions = ISC_LOG_MAX_VERSIONS;
-               }
-               /*
-                * First we fill 'to_keep' structure using insertion sort
-                */
-               memset(to_keep, 0, sizeof(to_keep));
-               while (isc_dir_read(&dir) == ISC_R_SUCCESS) {
-                       if (dir.entry.length > bnamelen &&
-                           strncmp(dir.entry.name, bname, bnamelen) == 0 &&
-                           dir.entry.name[bnamelen] == '.')
-                       {
-                               char *ename = &dir.entry.name[bnamelen + 1];
-                               version = strtoull(ename, &digit_end, 10);
-                               if (*digit_end == '\0') {
-                                       int i = 0;
-                                       while (i < versions &&
-                                              version < to_keep[i]) {
-                                               i++;
-                                       }
-                                       if (i < versions) {
-                                               memmove(&to_keep[i + 1],
-                                                       &to_keep[i],
-                                                       sizeof(to_keep[0]) *
-                                                               (versions - i -
-                                                                1));
-                                               to_keep[i] = version;
-                                       }
-                               }
-                       }
-               }
-
-               /*
-                * to_keep[versions - 1] is the last one we want to keep
-                */
-               last = to_keep[versions - 1];
-               isc_dir_reset(&dir);
-       }
+       last = last_to_keep(versions, &dir, bname, bnamelen);
 
        /*
         * Then we remove all files that we don't want to_keep