Modernize scandir(3) and alphasort(3) interfaces according to the IEEE

Std 1003.1-2008. Both Linux and Solaris conforms to the new definitions,
so we better follow too (older glibc used old BSDish alphasort prototype
and corresponding type of the comparision function for scandir). While
there, change the definitions of the functions to ANSI C and fix several
style issues nearby.

Remove requirement for "sys/types.h" include for functions from manpage.

POSIX also requires that alphasort(3) sorts as if strcoll(3) was used,
but leave the strcmp(3) call in the function for now.

Adapt in-tree callers of scandir(3) to new declaration. The fact that
select_sections() from catman(1) could modify supplied struct dirent is
a bug.

PR:	standards/142255
MFC after:	2 weeks

include/dirent.h

@@ -95,7 +95,7 @@ typedef	void *	DIR;
 __BEGIN_DECLS
 #if __BSD_VISIBLE
 DIR	*__opendir2(const char *, int);
-int	 alphasort(const void *, const void *);
+int	 alphasort(const struct dirent **, const struct dirent **);
 int	 getdents(int, char *, int);
 int	 getdirentries(int, char *, int, long *);
 #endif
@@ -109,7 +109,8 @@ int	 readdir_r(DIR *, struct dirent *, struct dirent **);
 void	 rewinddir(DIR *);
 #if __BSD_VISIBLE
 int	 scandir(const char *, struct dirent ***,
-	    int (*)(struct dirent *), int (*)(const void *, const void *));
+	    int (*)(const struct dirent *), int (*)(const struct dirent **,
+	    const struct dirent **));
 #endif
 #if __XSI_VISIBLE
 void	 seekdir(DIR *, long);

lib/libc/gen/opendir.c

@@ -240,7 +240,8 @@ __opendir_common(int fd, const char *name, int flags)
 				/*
 				 * This sort must be stable.
 				 */
-				mergesort(dpv, n, sizeof(*dpv), alphasort);
+				mergesort(dpv, n, sizeof(*dpv), (int (*)(const
+				    void *, const void *))alphasort);
 
 				dpv[n] = NULL;
 				xp = NULL;

lib/libc/gen/scandir.3

@@ -28,7 +28,7 @@
 .\"     @(#)scandir.3	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd June 4, 1993
+.Dd January 3, 2010
 .Dt SCANDIR 3
 .Os
 .Sh NAME
@@ -38,12 +38,11 @@
 .Sh LIBRARY
 .Lb libc
 .Sh SYNOPSIS
-.In sys/types.h
 .In dirent.h
 .Ft int
-.Fn scandir "const char *dirname" "struct dirent ***namelist" "int \\*(lp*select\\*(rp\\*(lpstruct dirent *\\*(rp" "int \\*(lp*compar\\*(rp\\*(lpconst void *, const void *\\*(rp"
+.Fn scandir "const char *dirname" "struct dirent ***namelist" "int \\*(lp*select\\*(rp\\*(lpconst struct dirent *\\*(rp" "int \\*(lp*compar\\*(rp\\*(lpconst struct dirent **, const struct dirent **\\*(rp"
 .Ft int
-.Fn alphasort "const void *d1" "const void *d2"
+.Fn alphasort "const struct dirent **d1" "const struct dirent **d2"
 .Sh DESCRIPTION
 The
 .Fn scandir

lib/libc/gen/scandir.c

@@ -58,11 +58,9 @@ __FBSDID("$FreeBSD$");
 	    (((dp)->d_namlen + 1 + 3) &~ 3))
 
 int
-scandir(dirname, namelist, select, dcomp)
-	const char *dirname;
-	struct dirent ***namelist;
-	int (*select)(struct dirent *);
-	int (*dcomp)(const void *, const void *);
+scandir(const char *dirname, struct dirent ***namelist,
+    int (*select)(const struct dirent *), int (*dcomp)(const struct dirent **,
+	const struct dirent **))
 {
 	struct dirent *d, *p, **names = NULL;
 	size_t nitems = 0;
@@ -111,26 +109,25 @@ scandir(dirname, namelist, select, dcomp)
 	}
 	closedir(dirp);
 	if (nitems && dcomp != NULL)
-		qsort(names, nitems, sizeof(struct dirent *), dcomp);
+		qsort(names, nitems, sizeof(struct dirent *),
+		    (int (*)(const void *, const void *))dcomp);
 	*namelist = names;
-	return(nitems);
+	return (nitems);
 
 fail:
 	while (nitems > 0)
 		free(names[--nitems]);
 	free(names);
 	closedir(dirp);
-	return -1;
+	return (-1);
 }
 
 /*
  * Alphabetic order comparison routine for those who want it.
  */
 int
-alphasort(d1, d2)
-	const void *d1;
-	const void *d2;
+alphasort(const struct dirent **d1, const struct dirent **d2)
 {
-	return(strcmp((*(struct dirent **)d1)->d_name,
-	    (*(struct dirent **)d2)->d_name));
+
+	return (strcmp((*d1)->d_name, (*d2)->d_name));
 }

usr.bin/catman/catman.c

@@ -589,9 +589,15 @@ process_section(char *mandir, char *section)
 }
 
 static int
-select_sections(struct dirent *entry)
+select_sections(const struct dirent *entry)
 {
-	return directory_type(entry->d_name) == MAN_SECTION_DIR;
+	char *name;
+	int ret;
+
+	name = strdup(entry->d_name);
+	ret = directory_type(name) == MAN_SECTION_DIR;
+	free(name);
+	return (ret);
 }
 
 /*

usr.bin/makewhatis/makewhatis.c

@@ -879,9 +879,9 @@ process_section(char *section_dir)
  * Returns whether the directory entry is a man page section.
  */
 static int
-select_sections(struct dirent *entry)
+select_sections(const struct dirent *entry)
 {
-	char *p = &entry->d_name[3];
+	const char *p = &entry->d_name[3];
 
 	if (strncmp(entry->d_name, "man", 3) != 0)
 		return 0;

usr.sbin/lpr/common_source/lp.h

@@ -280,7 +280,7 @@ void	 inform(const struct printer *_pp, char *_cf);
 void	 init_printer(struct printer *_pp);
 void	 init_request(struct request *_rp);
 int	 inlist(char *_uname, char *_cfile);
-int	 iscf(struct dirent *_d);
+int	 iscf(const struct dirent *_d);
 void	 ldump(const char *_nfile, const char *_datafile, int _copies);
 void	 lastprinter(void);
 int	 lockchk(struct printer *_pp, char *_slockf);

usr.sbin/lpr/common_source/rmjob.c

@@ -384,7 +384,7 @@ rmremote(const struct printer *pp)
  * Return 1 if the filename begins with 'cf'
  */
 int
-iscf(struct dirent *d)
+iscf(const struct dirent *d)
 {
 	return(d->d_name[0] == 'c' && d->d_name[1] == 'f');
 }