Rename sample_group plugin to group_file.

Install group_file and system_group plugins by default.

plugins/group_file/getgrent.c

@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2005,2008,2010-2013 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * Trivial replacements for the libc getgr{uid,nam}() routines.
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <stdio.h>
+#ifdef STDC_HEADERS
+# include <stdlib.h>
+# include <stddef.h>
+#else
+# ifdef HAVE_STDLIB_H
+#  include <stdlib.h>
+# endif
+#endif /* STDC_HEADERS */
+#ifdef HAVE_STRING_H
+# if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
+#  include <memory.h>
+# endif
+# include <string.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#include <fcntl.h>
+#include <limits.h>
+#include <pwd.h>
+#include <grp.h>
+
+#include "missing.h"
+
+#ifndef LINE_MAX
+# define LINE_MAX 2048
+#endif
+
+#undef GRMEM_MAX
+#define GRMEM_MAX 200
+
+static FILE *grf;
+static const char *grfile = "/etc/group";
+static int gr_stayopen;
+
+void mysetgrfile(const char *);
+void mysetgrent(void);
+void myendgrent(void);
+struct group *mygetgrent(void);
+struct group *mygetgrnam(const char *);
+struct group *mygetgrgid(gid_t);
+
+void
+mysetgrfile(const char *file)
+{
+    grfile = file;
+    if (grf != NULL)
+	myendgrent();
+}
+
+void
+mysetgrent(void)
+{
+    if (grf == NULL) {
+	grf = fopen(grfile, "r");
+	if (grf != NULL)
+	    fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
+    } else {
+	rewind(grf);
+    }
+    gr_stayopen = 1;
+}
+
+void
+myendgrent(void)
+{
+    if (grf != NULL) {
+	fclose(grf);
+	grf = NULL;
+    }
+    gr_stayopen = 0;
+}
+
+struct group *
+mygetgrent(void)
+{
+    static struct group gr;
+    static char grbuf[LINE_MAX], *gr_mem[GRMEM_MAX+1];
+    size_t len;
+    char *cp, *colon;
+    int n;
+
+    if ((colon = fgets(grbuf, sizeof(grbuf), grf)) == NULL)
+	return NULL;
+
+    memset(&gr, 0, sizeof(gr));
+    if ((colon = strchr(cp = colon, ':')) == NULL)
+	return NULL;
+    *colon++ = '\0';
+    gr.gr_name = cp;
+    if ((colon = strchr(cp = colon, ':')) == NULL)
+	return NULL;
+    *colon++ = '\0';
+    gr.gr_passwd = cp;
+    if ((colon = strchr(cp = colon, ':')) == NULL)
+	return NULL;
+    *colon++ = '\0';
+    gr.gr_gid = atoi(cp);
+    len = strlen(colon);
+    if (len > 0 && colon[len - 1] == '\n')
+	colon[len - 1] = '\0';
+    if (*colon != '\0') {
+	gr.gr_mem = gr_mem;
+	cp = strtok(colon, ",");
+	for (n = 0; cp != NULL && n < GRMEM_MAX; n++) {
+	    gr.gr_mem[n] = cp;
+	    cp = strtok(NULL, ",");
+	}
+	gr.gr_mem[n++] = NULL;
+    } else
+	gr.gr_mem = NULL;
+    return &gr;
+}
+
+struct group *
+mygetgrnam(const char *name)
+{
+    struct group *gr;
+
+    if (grf == NULL) {
+	if ((grf = fopen(grfile, "r")) == NULL)
+	    return NULL;
+	fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
+    } else {
+	rewind(grf);
+    }
+    while ((gr = mygetgrent()) != NULL) {
+	if (strcmp(gr->gr_name, name) == 0)
+	    break;
+    }
+    if (!gr_stayopen) {
+	fclose(grf);
+	grf = NULL;
+    }
+    return gr;
+}
+
+struct group *
+mygetgrgid(gid_t gid)
+{
+    struct group *gr;
+
+    if (grf == NULL) {
+	if ((grf = fopen(grfile, "r")) == NULL)
+	    return NULL;
+	fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
+    } else {
+	rewind(grf);
+    }
+    while ((gr = mygetgrent()) != NULL) {
+	if (gr->gr_gid == gid)
+	    break;
+    }
+    if (!gr_stayopen) {
+	fclose(grf);
+	grf = NULL;
+    }
+    return gr;
+}