On 02/11/15 11:41, Andrew Gregory wrote:
If given size 0 POSIX allows realloc to return a pointer that is not suitable for use.
From malloc(3):
"if size is equal to zero, and ptr is not NULL, then the call is equivalent to free(ptr)." Is that not generally guaranteed? Or is qsort the issue here?
Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com> --- lib/libalpm/be_local.c | 10 +++++++--- lib/libalpm/be_sync.c | 10 +++++++--- 2 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/lib/libalpm/be_local.c b/lib/libalpm/be_local.c index 556157d..e35fc0e 100644 --- a/lib/libalpm/be_local.c +++ b/lib/libalpm/be_local.c @@ -810,9 +810,13 @@ static int local_db_read(alpm_pkg_t *info, alpm_dbinfrq_t inforeq) files_count++; } /* attempt to hand back any memory we don't need */ - files = realloc(files, sizeof(alpm_file_t) * files_count); - /* make sure the list is sorted */ - qsort(files, files_count, sizeof(alpm_file_t), _alpm_files_cmp); + if(files_count > 0) { + files = realloc(files, sizeof(alpm_file_t) * files_count); + /* make sure the list is sorted */ + qsort(files, files_count, sizeof(alpm_file_t), _alpm_files_cmp); + } else { + FREE(files); + } info->files.count = files_count; info->files.files = files; } else if(strcmp(line, "%BACKUP%") == 0) { diff --git a/lib/libalpm/be_sync.c b/lib/libalpm/be_sync.c index 25c8cbe..b09b060 100644 --- a/lib/libalpm/be_sync.c +++ b/lib/libalpm/be_sync.c @@ -721,9 +721,13 @@ static int sync_db_read(alpm_db_t *db, struct archive *archive, files_count++; } /* attempt to hand back any memory we don't need */ - files = realloc(files, sizeof(alpm_file_t) * files_count); - /* make sure the list is sorted */ - qsort(files, files_count, sizeof(alpm_file_t), _alpm_files_cmp); + if(files_count > 0) { + files = realloc(files, sizeof(alpm_file_t) * files_count); + /* make sure the list is sorted */ + qsort(files, files_count, sizeof(alpm_file_t), _alpm_files_cmp); + } else { + FREE(files); + } pkg->files.count = files_count; pkg->files.files = files; }