simplify a few accesses to fields of structs, using auxiliary pointer

[mandoc.git] / compat_fts.c

diff --git a/compat_fts.c b/compat_fts.c
index 65caa8510cd7c72b5c7080a5c89d702fc48f9ef0..e44298df02b84359eb2c38e76144fad36e8d491d 100644 (file)
--- a/compat_fts.c
+++ b/compat_fts.c
@@ -1,13 +1,5 @@
-#include "config.h"
-
-#if HAVE_FTS
-
-int dummy;
-
-#else
-
-/*     $Id: compat_fts.c,v 1.11 2016/10/18 23:13:25 schwarze Exp $     */
-/*     $OpenBSD: fts.c,v 1.56 2016/09/21 04:38:56 guenther Exp $       */
+/*     $Id: compat_fts.c,v 1.17 2020/06/15 01:37:14 schwarze Exp $     */
+/*     $OpenBSD: fts.c,v 1.59 2019/06/28 13:32:41 deraadt Exp $        */
 
 /*-
  * Copyright (c) 1990, 1993, 1994
@@ -37,6 +29,7 @@ int dummy;
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+#include "config.h"
 
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -59,30 +52,28 @@ static void  fts_load(FTS *, FTSENT *);
 static size_t   fts_maxarglen(char * const *);
 static void     fts_padjust(FTS *, FTSENT *);
 static int      fts_palloc(FTS *, size_t);
+static FTSENT  *fts_sort(FTS *, FTSENT *, int);
 static unsigned short   fts_stat(FTS *, FTSENT *);
 
+typedef int (*qsort_compar_proto)(const void *, const void *);
+
 #define        ISDOT(a)        (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
-#ifndef        O_DIRECTORY
-#define        O_DIRECTORY     0
-#endif
 #ifndef        O_CLOEXEC
 #define        O_CLOEXEC       0
 #endif
-#ifndef        PATH_MAX
-#define        PATH_MAX        4096
-#endif
 
 #define        CLR(opt)        (sp->fts_options &= ~(opt))
 #define        ISSET(opt)      (sp->fts_options & (opt))
 #define        SET(opt)        (sp->fts_options |= (opt))
 
 FTS *
-fts_open(char * const *argv, int options, void *dummy)
+fts_open(char * const *argv, int options,
+    int (*compar)(const FTSENT **, const FTSENT **))
 {
        FTS *sp;
        FTSENT *p, *root;
        int nitems;
-       FTSENT *parent, *tmp;
+       FTSENT *parent, *prev;
 
        /* Options check. */
        if (options & ~FTS_OPTIONMASK) {
@@ -99,6 +90,7 @@ fts_open(char * const *argv, int options, void *dummy)
        /* Allocate/initialize the stream */
        if ((sp = calloc(1, sizeof(FTS))) == NULL)
                return (NULL);
+       sp->fts_compar = compar;
        sp->fts_options = options;
 
        /*
@@ -114,7 +106,7 @@ fts_open(char * const *argv, int options, void *dummy)
        parent->fts_level = FTS_ROOTPARENTLEVEL;
 
        /* Allocate/initialize root(s). */
-       for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) {
+       for (root = prev = NULL, nitems = 0; *argv; ++argv, ++nitems) {
                if ((p = fts_alloc(sp, *argv, strlen(*argv))) == NULL)
                        goto mem3;
                p->fts_level = FTS_ROOTLEVEL;
@@ -126,14 +118,24 @@ fts_open(char * const *argv, int options, void *dummy)
                if (p->fts_info == FTS_DOT)
                        p->fts_info = FTS_D;
 
-               p->fts_link = NULL;
-               if (root == NULL)
-                       tmp = root = p;
-               else {
-                       tmp->fts_link = p;
-                       tmp = p;
+               /*
+                * If comparison routine supplied, traverse in sorted
+                * order; otherwise traverse in the order specified.
+                */
+               if (compar) {
+                       p->fts_link = root;
+                       root = p;
+               } else {
+                       p->fts_link = NULL;
+                       if (root == NULL)
+                               root = p;
+                       else
+                               prev->fts_link = p;
+                       prev = p;
                }
        }
+       if (compar && nitems > 1)
+               root = fts_sort(sp, root, nitems);
 
        /*
         * Allocate a dummy pointer and make fts_read think that we've just
@@ -203,6 +205,7 @@ fts_close(FTS *sp)
        /* Free up child linked list, sort array, path buffer, stream ptr.*/
        if (sp->fts_child)
                fts_lfree(sp->fts_child);
+       free(sp->fts_array);
        free(sp->fts_path);
        free(sp);
 
@@ -490,6 +493,10 @@ mem1:                              saved_errno = errno;
                cur->fts_info = FTS_DP;
                return (NULL);
        }
+
+       /* Sort the entries. */
+       if (sp->fts_compar && nitems > 1)
+               head = fts_sort(sp, head, nitems);
        return (head);
 }
 
@@ -546,6 +553,41 @@ fts_stat(FTS *sp, FTSENT *p)
        return (FTS_DEFAULT);
 }
 
+static FTSENT *
+fts_sort(FTS *sp, FTSENT *head, int nitems)
+{
+       FTSENT **ap, *p;
+
+       /*
+        * Construct an array of pointers to the structures and call qsort(3).
+        * Reassemble the array in the order returned by qsort.  If unable to
+        * sort for memory reasons, return the directory entries in their
+        * current order.  Allocate enough space for the current needs plus
+        * 40 so don't realloc one entry at a time.
+        */
+       if (nitems > sp->fts_nitems) {
+               struct _ftsent **a;
+
+               if ((a = reallocarray(sp->fts_array,
+                   nitems + 40, sizeof(FTSENT *))) == NULL) {
+                       free(sp->fts_array);
+                       sp->fts_array = NULL;
+                       sp->fts_nitems = 0;
+                       return (head);
+               }
+               sp->fts_nitems = nitems + 40;
+               sp->fts_array = a;
+       }
+       for (ap = sp->fts_array, p = head; p; p = p->fts_link)
+               *ap++ = p;
+       qsort(sp->fts_array, nitems, sizeof(FTSENT *),
+           (qsort_compar_proto)sp->fts_compar);
+       for (head = *(ap = sp->fts_array); --nitems; ++ap)
+               ap[0]->fts_link = ap[1];
+       ap[0]->fts_link = NULL;
+       return (head);
+}
+
 static FTSENT *
 fts_alloc(FTS *sp, const char *name, size_t namelen)
 {
@@ -602,13 +644,14 @@ fts_palloc(FTS *sp, size_t more)
                errno = ENAMETOOLONG;
                return (1);
        }
-       sp->fts_pathlen += more;
-       p = realloc(sp->fts_path, sp->fts_pathlen);
+       p = recallocarray(sp->fts_path, sp->fts_pathlen,
+           sp->fts_pathlen + more, 1);
        if (p == NULL) {
                free(sp->fts_path);
                sp->fts_path = NULL;
                return (1);
        }
+       sp->fts_pathlen += more;
        sp->fts_path = p;
        return (0);
 }
@@ -651,5 +694,3 @@ fts_maxarglen(char * const *argv)
                        max = len;
        return (max + 1);
 }
-
-#endif