Simplify string handling

contrib/adduser.c

@@ -119,6 +119,7 @@
 #include <syslog.h>
 
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 
 
 #define IMMEDIATE_CHANGE	/* Expire newly created password, must be changed
@@ -224,7 +225,7 @@ main (void)
 	      printf ("That name is in use, choose another.\n");
 	      done = 0;
 	    }
-	  else if (strchr (usrname, ' ') != NULL)
+	  else if (strchr(usrname, ' '))
 	    {
 	      printf ("No spaces in username!!\n");
 	      done = 0;
@@ -389,7 +390,7 @@ main (void)
       fflush (stdout);
       safeget (foo, sizeof (foo));
 
-      done = bad = correct = (foo[0] == 'y' || foo[0] == 'Y');
+      done = bad = correct = (strprefix(foo, "y") || strprefix(foo, "Y"));
 
       if (bad != 1)
 	printf ("\nUser [%s] not added\n", usrname);

lib/Makefile.am

@@ -206,6 +206,8 @@ libshadow_la_SOURCES = \
 	string/strchr/strrspn.h \
 	string/strcmp/streq.c \
 	string/strcmp/streq.h \
+	string/strcmp/strprefix.c \
+	string/strcmp/strprefix.h \
 	string/strcpy/stpecpy.c \
 	string/strcpy/stpecpy.h \
 	string/strcpy/strncat.c \

lib/chkname.c

@@ -73,9 +73,9 @@ is_valid_name(const char *name)
          */
 	int numeric;
 
-	if ('\0' == *name ||
-	    ('.' == *name && (('.' == name[1] && '\0' == name[2]) ||
-			      '\0' == name[1])) ||
+	if (streq(name, "") ||
+	    streq(name, ".") ||
+	    streq(name, "..") ||
 	    !((*name >= 'a' && *name <= 'z') ||
 	      (*name >= 'A' && *name <= 'Z') ||
 	      (*name >= '0' && *name <= '9') ||
@@ -95,7 +95,7 @@ is_valid_name(const char *name)
 		      *name == '_' ||
 		      *name == '.' ||
 		      *name == '-' ||
-		      (*name == '$' && name[1] == '\0')
+		      streq(name, "$")
 		     ))
 		{
 			errno = EINVAL;

lib/commonio.c

@@ -37,6 +37,7 @@
 #include "string/memset/memzero.h"
 #include "string/sprintf/snprintf.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strtok/stpsep.h"
 
 
@@ -524,7 +525,7 @@ static void add_one_entry (struct commonio_db *db,
 
 static bool name_is_nis (const char *name)
 {
-	return (('+' == name[0]) || ('-' == name[0]));
+	return strprefix(name, "+") || strprefix(name, "-");
 }
 
 

lib/console.c

@@ -17,6 +17,7 @@
 #include "getdef.h"
 #include "prototypes.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strcpy/strtcpy.h"
 #include "string/strtok/stpsep.h"
 
@@ -103,9 +104,7 @@ is_listed(const char *cfgin, const char *tty, bool def)
 
 bool console (const char *tty)
 {
-	if (strncmp (tty, "/dev/", 5) == 0) {
-		tty += 5;
-	}
+	tty = strprefix(tty, "/dev/") ?: tty;
 
 	return is_listed ("CONSOLE", tty, true);
 }

lib/copydir.c

@@ -40,6 +40,7 @@
 #include "shadowlog.h"
 #include "string/sprintf/xasprintf.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 
 
 static /*@null@*/const char *src_orig;
@@ -576,7 +577,7 @@ static int copy_symlink (const struct path_info *src, const struct path_info *ds
 	 * create a link to the corresponding entry in the dst_orig
 	 * directory.
 	 */
-	if (strncmp(oldlink, src_orig, strlen(src_orig)) == 0) {
+	if (strprefix(oldlink, src_orig)) {
 		char  *dummy;
 
 		xasprintf(&dummy, "%s%s", dst_orig, oldlink + strlen(src_orig));

lib/encrypt.c

@@ -17,6 +17,8 @@
 #include "prototypes.h"
 #include "defines.h"
 #include "shadowlog_internal.h"
+#include "string/strcmp/strprefix.h"
+
 
 /*@exposed@*//*@null@*/char *pw_encrypt (const char *clear, const char *salt)
 {
@@ -35,7 +37,7 @@
 
 	/* Some crypt() do not return NULL if the algorithm is not
 	 * supported, and return a DES encrypted password. */
-	if ((NULL != salt) && (salt[0] == '$') && (strlen (cp) <= 13))
+	if ((NULL != salt) && strprefix(salt, "$") && (strlen (cp) <= 13))
 	{
 		/*@observer@*/const char *method;
 		switch (salt[1])

lib/env.c

@@ -23,6 +23,7 @@
 #include "shadowlog.h"
 #include "string/sprintf/snprintf.h"
 #include "string/sprintf/xasprintf.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strdup/xstrdup.h"
 
 
@@ -175,7 +176,7 @@ void set_env (int argc, char *const *argv)
 			const char *const *p;
 
 			for (p = forbid; NULL != *p; p++) {
-				if (strncmp (*argv, *p, strlen (*p)) == 0) {
+				if (strprefix(*argv, *p)) {
 					break;
 				}
 			}
@@ -210,7 +211,7 @@ void sanitize_env (void)
 
 	for (cur = envp; NULL != *cur; cur++) {
 		for (bad = forbid; NULL != *bad; bad++) {
-			if (strncmp (*cur, *bad, strlen (*bad)) == 0) {
+			if (strprefix(*cur, *bad)) {
 				for (move = cur; NULL != *move; move++) {
 					*move = *(move + 1);
 				}
@@ -222,12 +223,12 @@ void sanitize_env (void)
 
 	for (cur = envp; NULL != *cur; cur++) {
 		for (bad = noslash; NULL != *bad; bad++) {
-			if (strncmp (*cur, *bad, strlen (*bad)) != 0) {
+			if (!strprefix(*cur, *bad)) {
 				continue;
 			}
-			if (strchr (*cur, '/') == NULL) {
+			if (!strchr(*cur, '/'))
 				continue;	/* OK */
-			}
+
 			for (move = cur; NULL != *move; move++) {
 				*move = *(move + 1);
 			}

lib/getdate.y

@@ -33,6 +33,7 @@
 #include "getdate.h"
 #include "string/strchr/stpspn.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 
 
 /* Some old versions of bison generate parsers that use bcopy.
@@ -657,7 +658,7 @@ static int LookupWord (char *buff)
     {
       if (abbrev)
 	{
-	  if (strncmp (buff, tp->name, 3) == 0)
+	  if (strprefix(tp->name, buff))
 	    {
 	      yylval.Number = tp->value;
 	      return tp->type;

lib/getdef.c

@@ -33,6 +33,7 @@
 #include "string/strchr/stpspn.h"
 #include "string/strchr/strrspn.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strtok/stpsep.h"
 
 
@@ -567,7 +568,7 @@ static void def_load (void)
 		 * Break the line into two fields.
 		 */
 		name = stpspn(buf, " \t");	/* first nonwhite */
-		if (streq(name, "") || *name == '#')
+		if (streq(name, "") || strprefix(name, "#"))
 			continue;	/* comment or empty */
 
 		s = stpsep(name, " \t");  /* next field */

lib/limits.c

@@ -38,6 +38,7 @@
 #include "string/memset/memzero.h"
 #include "string/strchr/stpspn.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "typetraits.h"
 
 
@@ -62,7 +63,7 @@
 	/* The "-" is special, not belonging to a strange negative limit.
 	 * It is infinity, in a controlled way.
 	 */
-	if ('-' == value[0]) {
+	if (strprefix(value, "-")) {
 		limit = RLIM_INFINITY;
 
 	} else {
@@ -370,7 +371,7 @@
 	 * FIXME: A better (smarter) checking should be done
 	 */
 	while (fgets (buf, 1024, fil) != NULL) {
-		if (('#' == buf[0]) || ('\n' == buf[0])) {
+		if (strprefix(buf, "#") || strprefix(buf, "\n")) {
 			continue;
 		}
 		MEMZERO(tempbuf);
@@ -401,7 +402,7 @@
 				break;
 			} else if (streq(name, "*")) {
 				strcpy (deflimits, tempbuf);
-			} else if (name[0] == '@') {
+			} else if (strprefix(name, "@")) {
 				/* If the user is in the group, the group
 				 * limits apply unless later a line for
 				 * the specific user is found.
@@ -473,14 +474,15 @@
 			}
 		}
 		for (cp = info->pw_gecos; cp != NULL; cp = strchr (cp, ',')) {
-			if (',' == *cp) {
-				cp++;
-			}
+			char  *val;
+
+			cp = strprefix(cp, ",") ?: cp;
 
-			if (strncmp (cp, "pri=", 4) == 0) {
+			val = strprefix(cp, "pri=");
+			if (val != NULL) {
 				int  inc;
 
-				if (a2si(&inc, cp + 4, NULL, 0, -20, 20) == 0) {
+				if (a2si(&inc, val, NULL, 0, -20, 20) == 0) {
 					errno = 0;
 					if (   (nice (inc) != -1)
 					    || (0 != errno)) {
@@ -495,21 +497,25 @@
 
 				continue;
 			}
-			if (strncmp (cp, "ulimit=", 7) == 0) {
+
+			val = strprefix(cp, "ulimit=");
+			if (val != NULL) {
 				int  blocks;
 
-				if (   (str2si(&blocks, cp + 7) == -1)
+				if (   (str2si(&blocks, val) == -1)
 				    || (set_filesize_limit (blocks) != 0)) {
 					SYSLOG ((LOG_WARN,
 					         "Can't set the ulimit for user %s",
 					         info->pw_name));
 				}
 				continue;
 			}
-			if (strncmp (cp, "umask=", 6) == 0) {
+
+			val = strprefix(cp, "umask=");
+			if (val != NULL) {
 				mode_t  mask;
 
-				if (str2i(mode_t, &mask, cp + 6) == -1) {
+				if (str2i(mode_t, &mask, val) == -1) {
 					SYSLOG ((LOG_WARN,
 					         "Can't set umask value for user %s",
 					         info->pw_name));

lib/nss.c

@@ -17,6 +17,7 @@
 #include "string/sprintf/snprintf.h"
 #include "string/strchr/stpspn.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strtok/stpsep.h"
 
 
@@ -79,7 +80,7 @@ nss_init(const char *nsswitch_path) {
 	}
 	p = NULL;
 	while (getline(&line, &len, nssfp) != -1) {
-		if (line[0] == '#')
+		if (strprefix(line, "#"))
 			continue;
 		if (strlen(line) < 8)
 			continue;

lib/obscure.c

@@ -14,6 +14,7 @@
 
 #include <ctype.h>
 #include <stdio.h>
+#include <string.h>
 
 #include "attr.h"
 #include "prototypes.h"
@@ -66,9 +67,8 @@ static bool similar (/*@notnull@*/const char *old, /*@notnull@*/const char *new)
 	}
 
 	for (i = j = 0; ('\0' != new[i]) && ('\0' != old[i]); i++) {
-		if (strchr (new, old[i]) != NULL) {
+		if (strchr(new, old[i]))
 			j++;
-		}
 	}
 
 	if (i >= j * 2) {

lib/port.c

@@ -20,6 +20,7 @@
 #include "port.h"
 #include "prototypes.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 #include "string/strtok/stpsep.h"
 
 
@@ -50,7 +51,7 @@ static int portcmp (const char *pattern, const char *port)
 	if (streq(orig, "SU"))
 		return 1;
 
-	return (*pattern == '*') ? 0 : 1;
+	return !strprefix(pattern, "*");
 }
 
 /*
@@ -140,7 +141,7 @@ getportent(void)
 		errno = saveerr;
 		return NULL;
 	}
-	if ('#' == buf[0])
+	if (strprefix(buf, "#"))
 		goto next;
 
 	stpsep(buf, "\n");

lib/prefix_flag.c

@@ -30,6 +30,7 @@
 #include "shadowlog.h"
 #include "string/sprintf/xasprintf.h"
 #include "string/strcmp/streq.h"
+#include "string/strcmp/strprefix.h"
 
 
 static char *passwd_db_file = NULL;
@@ -53,17 +54,15 @@
  */
 extern const char* process_prefix_flag (const char* short_opt, int argc, char **argv)
 {
-	/*
-	 * Parse the command line options.
-	 */
-	int i;
-	const char *prefix = NULL, *val;
-
-	for (i = 0; i < argc; i++) {
-		val = NULL;
+	const char *prefix = NULL;
+
+	for (int i = 0; i < argc; i++) {
+		const char  *val;
+
+		val = strprefix(argv[i], "--prefix=");
+
 		if (   streq(argv[i], "--prefix")
-		    || ((strncmp (argv[i], "--prefix=", 9) == 0)
-			&& (val = argv[i] + 9))
+		    || val != NULL
 		    || streq(argv[i], short_opt))
 		{
 			if (NULL != prefix) {
@@ -82,7 +81,7 @@
 				exit (E_BAD_ARG);
 			} else {
 				prefix = argv[++ i];
 			}
 		}
 	}