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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/patch/backupfile.c	Lines:	29	69	42.0 %
Date:	2016-12-06	Branches:	12	52	23.1 %


/*	$OpenBSD: backupfile.c,v 1.21 2013/11/26 13:19:07 deraadt Exp $	*/

/*
 * backupfile.c -- make Emacs style backup file names Copyright (C) 1990 Free
 * Software Foundation, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * without restriction.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.
 */

/*
 * David MacKenzie <djm@ai.mit.edu>. Some algorithms adapted from GNU Emacs.
 */

#include <ctype.h>
#include <dirent.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "backupfile.h"


#define ISDIGIT(c) (isascii (c) && isdigit (c))

/* Which type of backup file names are generated. */
enum backup_type backup_type = none;

/*
 * The extension added to file names to produce a simple (as opposed to
 * numbered) backup file name.
 */
char		*simple_backup_suffix = "~";

static char	*concat(const char *, const char *);
static char	*make_version_name(const char *, int);
static int	max_backup_version(const char *, const char *);
static int	version_number(const char *, const char *, size_t);
static int	argmatch(const char *, const char **);
static void	invalid_arg(const char *, const char *, int);

/*
 * Return the name of the new backup file for file FILE, allocated with
 * malloc.  Return 0 if out of memory. FILE must not end with a '/' unless it
 * is the root directory. Do not call this function if backup_type == none.
 */
char *
find_backup_file_name(const char *file)
{
	char	*dir, *base_versions;
	int	highest_backup;

	if (backup_type == simple)
		return concat(file, simple_backup_suffix);
	base_versions = concat(basename(file), ".~");
	if (base_versions == NULL)
		return NULL;
	dir = dirname(file);
	if (dir == NULL) {
		free(base_versions);
		return NULL;
	}
	highest_backup = max_backup_version(base_versions, dir);
	free(base_versions);
	if (backup_type == numbered_existing && highest_backup == 0)
		return concat(file, simple_backup_suffix);
	return make_version_name(file, highest_backup + 1);
}

/*
 * Return the number of the highest-numbered backup file for file FILE in
 * directory DIR.  If there are no numbered backups of FILE in DIR, or an
 * error occurs reading DIR, return 0. FILE should already have ".~" appended
 * to it.
 */
static int
max_backup_version(const char *file, const char *dir)
{
	DIR	*dirp;
	struct dirent	*dp;
	int	highest_version, this_version;
	size_t	file_name_length;

	dirp = opendir(dir);
	if (dirp == NULL)
		return 0;

	highest_version = 0;
	file_name_length = strlen(file);

	while ((dp = readdir(dirp)) != NULL) {
		if (dp->d_namlen <= file_name_length)
			continue;

		this_version = version_number(file, dp->d_name, file_name_length);
		if (this_version > highest_version)
			highest_version = this_version;
	}
	closedir(dirp);
	return highest_version;
}

/*
 * Return a string, allocated with malloc, containing "FILE.~VERSION~".
 * Return 0 if out of memory.
 */
static char *
make_version_name(const char *file, int version)
{
	char	*backup_name;

	if (asprintf(&backup_name, "%s.~%d~", file, version) == -1)
		return NULL;
	return backup_name;
}

/*
 * If BACKUP is a numbered backup of BASE, return its version number;
 * otherwise return 0.  BASE_LENGTH is the length of BASE. BASE should
 * already have ".~" appended to it.
 */
static int
version_number(const char *base, const char *backup, size_t base_length)
{
	int		version;
	const char	*p;

	version = 0;
	if (!strncmp(base, backup, base_length) &&
	    ISDIGIT((unsigned char)backup[base_length])) {
		for (p = &backup[base_length]; ISDIGIT((unsigned char)*p); ++p)
			version = version * 10 + *p - '0';
		if (p[0] != '~' || p[1])
			version = 0;
	}
	return version;
}

/*
 * Return the newly-allocated concatenation of STR1 and STR2. If out of
 * memory, return 0.
 */
static char  *
concat(const char *str1, const char *str2)
{
	char	*newstr;

	if (asprintf(&newstr, "%s%s", str1, str2) == -1)
		return NULL;
	return newstr;
}

/*
 * If ARG is an unambiguous match for an element of the null-terminated array
 * OPTLIST, return the index in OPTLIST of the matched element, else -1 if it
 * does not match any element or -2 if it is ambiguous (is a prefix of more
 * than one element).
 */
static int
argmatch(const char *arg, const char **optlist)
{
	int	i;	/* Temporary index in OPTLIST. */
	size_t	arglen;	/* Length of ARG. */
	int	matchind = -1;	/* Index of first nonexact match. */
	int	ambiguous = 0;	/* If nonzero, multiple nonexact match(es). */

	arglen = strlen(arg);

	/* Test all elements for either exact match or abbreviated matches.  */
	for (i = 0; optlist[i]; i++) {
		if (!strncmp(optlist[i], arg, arglen)) {
			if (strlen(optlist[i]) == arglen)
				/* Exact match found.  */
				return i;
			else if (matchind == -1)
				/* First nonexact match found.  */
				matchind = i;
			else
				/* Second nonexact match found.  */
				ambiguous = 1;
		}
	}
	if (ambiguous)
		return -2;
	else
		return matchind;
}

/*
 * Error reporting for argmatch. KIND is a description of the type of entity
 * that was being matched. VALUE is the invalid value that was given. PROBLEM
 * is the return value from argmatch.
 */
static void
invalid_arg(const char *kind, const char *value, int problem)
{
	fprintf(stderr, "patch: ");
	if (problem == -1)
		fprintf(stderr, "invalid");
	else			/* Assume -2. */
		fprintf(stderr, "ambiguous");
	fprintf(stderr, " %s `%s'\n", kind, value);
}

static const char *backup_args[] = {
	"never", "simple", "nil", "existing", "t", "numbered", 0
};

static enum backup_type backup_types[] = {
	simple, simple, numbered_existing,
	numbered_existing, numbered, numbered
};

/*
 * Return the type of backup indicated by VERSION. Unique abbreviations are
 * accepted.
 */
enum backup_type
get_version(const char *version)
{
	int	i;

	if (version == NULL || *version == '\0')
		return numbered_existing;
	i = argmatch(version, backup_args);
	if (i >= 0)
		return backup_types[i];
	invalid_arg("version control type", version, i);
	exit(2);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: backupfile.c,v 1.21 2013/11/26 13:19:07 deraadt Exp $ */
2
3			/*
4			* backupfile.c -- make Emacs style backup file names Copyright (C) 1990 Free
5			* Software Foundation, Inc.
6			*
7			* This program is free software; you can redistribute it and/or modify it
8			* without restriction.
9			*
10			* This program is distributed in the hope that it will be useful, but WITHOUT
11			* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12			* FITNESS FOR A PARTICULAR PURPOSE.
13			*/
14
15			/*
16			* David MacKenzie <djm@ai.mit.edu>. Some algorithms adapted from GNU Emacs.
17			*/
18
19			#include <ctype.h>
20			#include <dirent.h>
21			#include <libgen.h>
22			#include <stdio.h>
23			#include <stdlib.h>
24			#include <string.h>
25			#include <unistd.h>
26
27			#include "backupfile.h"
28
29
30			#define ISDIGIT(c) (isascii (c) && isdigit (c))
31
32			/* Which type of backup file names are generated. */
33			enum backup_type backup_type = none;
34
35			/*
36			* The extension added to file names to produce a simple (as opposed to
37			* numbered) backup file name.
38			*/
39			char *simple_backup_suffix = "~";
40
41			static char concat(const char , const char *);
42			static char make_version_name(const char , int);
43			static int max_backup_version(const char , const char );
44			static int version_number(const char , const char , size_t);
45			static int argmatch(const char , const char *);
46			static void invalid_arg(const char , const char , int);
47
48			/*
49			* Return the name of the new backup file for file FILE, allocated with
50			* malloc. Return 0 if out of memory. FILE must not end with a '/' unless it
51			* is the root directory. Do not call this function if backup_type == none.
52			*/
53			char *
54			find_backup_file_name(const char *file)
55		52	{
56			char dir, base_versions;
57			int highest_backup;
58
59	✗✓	52	if (backup_type == simple)
60			return concat(file, simple_backup_suffix);
61		52	base_versions = concat(basename(file), ".~");
62	✗✓	52	if (base_versions == NULL)
63			return NULL;
64		52	dir = dirname(file);
65	✗✓	52	if (dir == NULL) {
66			free(base_versions);
67			return NULL;
68			}
69		52	highest_backup = max_backup_version(base_versions, dir);
70		52	free(base_versions);
71	✓✗	52	if (backup_type == numbered_existing && highest_backup == 0)
72		52	return concat(file, simple_backup_suffix);
73			return make_version_name(file, highest_backup + 1);
74			}
75
76			/*
77			* Return the number of the highest-numbered backup file for file FILE in
78			* directory DIR. If there are no numbered backups of FILE in DIR, or an
79			* error occurs reading DIR, return 0. FILE should already have ".~" appended
80			* to it.
81			*/
82			static int
83			max_backup_version(const char file, const char dir)
84		52	{
85			DIR *dirp;
86			struct dirent *dp;
87			int highest_version, this_version;
88			size_t file_name_length;
89
90		52	dirp = opendir(dir);
91	✗✓	52	if (dirp == NULL)
92			return 0;
93
94		52	highest_version = 0;
95		52	file_name_length = strlen(file);
96
97	✓✓	6950	while ((dp = readdir(dirp)) != NULL) {
98	✓✓	6846	if (dp->d_namlen <= file_name_length)
99		5466	continue;
100
101		1380	this_version = version_number(file, dp->d_name, file_name_length);
102	✗✓	1380	if (this_version > highest_version)
103			highest_version = this_version;
104			}
105		52	closedir(dirp);
106		52	return highest_version;
107			}
108
109			/*
110			* Return a string, allocated with malloc, containing "FILE.~VERSION~".
111			* Return 0 if out of memory.
112			*/
113			static char *
114			make_version_name(const char *file, int version)
115			{
116			char *backup_name;
117
118			if (asprintf(&backup_name, "%s.~%d~", file, version) == -1)
119			return NULL;
120			return backup_name;
121			}
122
123			/*
124			* If BACKUP is a numbered backup of BASE, return its version number;
125			* otherwise return 0. BASE_LENGTH is the length of BASE. BASE should
126			* already have ".~" appended to it.
127			*/
128			static int
129			version_number(const char base, const char backup, size_t base_length)
130		1380	{
131			int version;
132			const char *p;
133
134		1380	version = 0;
135	✗✓✗✗ ✗✗	1380	if (!strncmp(base, backup, base_length) &&
136			ISDIGIT((unsigned char)backup[base_length])) {
137			for (p = &backup[base_length]; ISDIGIT((unsigned char)*p); ++p)
138			version = version * 10 + *p - '0';
139			if (p[0] != '~' \|\| p[1])
140			version = 0;
141			}
142		1380	return version;
143			}
144
145			/*
146			* Return the newly-allocated concatenation of STR1 and STR2. If out of
147			* memory, return 0.
148			*/
149			static char *
150			concat(const char str1, const char str2)
151		104	{
152			char *newstr;
153
154	✗✓	104	if (asprintf(&newstr, "%s%s", str1, str2) == -1)
155			return NULL;
156		104	return newstr;
157			}
158
159			/*
160			* If ARG is an unambiguous match for an element of the null-terminated array
161			* OPTLIST, return the index in OPTLIST of the matched element, else -1 if it
162			* does not match any element or -2 if it is ambiguous (is a prefix of more
163			* than one element).
164			*/
165			static int
166			argmatch(const char arg, const char *optlist)
167			{
168			int i; /* Temporary index in OPTLIST. */
169			size_t arglen; /* Length of ARG. */
170			int matchind = -1; /* Index of first nonexact match. */
171			int ambiguous = 0; /* If nonzero, multiple nonexact match(es). */
172
173			arglen = strlen(arg);
174
175			/* Test all elements for either exact match or abbreviated matches. */
176			for (i = 0; optlist[i]; i++) {
177			if (!strncmp(optlist[i], arg, arglen)) {
178			if (strlen(optlist[i]) == arglen)
179			/* Exact match found. */
180			return i;
181			else if (matchind == -1)
182			/* First nonexact match found. */
183			matchind = i;
184			else
185			/* Second nonexact match found. */
186			ambiguous = 1;
187			}
188			}
189			if (ambiguous)
190			return -2;
191			else
192			return matchind;
193			}
194
195			/*
196			* Error reporting for argmatch. KIND is a description of the type of entity
197			* that was being matched. VALUE is the invalid value that was given. PROBLEM
198			* is the return value from argmatch.
199			*/
200			static void
201			invalid_arg(const char kind, const char value, int problem)
202			{
203			fprintf(stderr, "patch: ");
204			if (problem == -1)
205			fprintf(stderr, "invalid");
206			else /* Assume -2. */
207			fprintf(stderr, "ambiguous");
208			fprintf(stderr, " %s `%s'\n", kind, value);
209			}
210
211			static const char *backup_args[] = {
212			"never", "simple", "nil", "existing", "t", "numbered", 0
213			};
214
215			static enum backup_type backup_types[] = {
216			simple, simple, numbered_existing,
217			numbered_existing, numbered, numbered
218			};
219
220			/*
221			* Return the type of backup indicated by VERSION. Unique abbreviations are
222			* accepted.
223			*/
224			enum backup_type
225			get_version(const char *version)
226			{
227			int i;
228
229			if (version == NULL \|\| *version == '\0')
230			return numbered_existing;
231			i = argmatch(version, backup_args);
232			if (i >= 0)
233			return backup_types[i];
234			invalid_arg("version control type", version, i);
235			exit(2);
236			}