1 #include <errno.h>
2 #include <stdarg.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <string.h>
6 #include <unistd.h>
7 
8 #define O_INTERACTIVE 1
9 #define O_NOACT (1<<1)
10 #define O_NOOVERRIDE (1<<2)
11 #define O_REPLACEALL (1<<3)
12 #define O_REPLACELAST (1<<4)
13 #define O_VERBOSE (1<<5)
14 
15 uint8_t opts;
16 
17 void
18 warn(const char *fmt, ...)
19 {
20 	char *w = strerror(errno);
21 	fputs("rene: ", stderr);
22 	if (fmt != NULL) {
23 		va_list argp;
24 		va_start(argp, fmt);
25 		vfprintf(stderr, fmt, argp);
26 		va_end(argp);
27 	}
28 	fprintf(stderr, ": %s\n", w);
29 }
30 
31 void
32 err(int eval, const char *fmt, ...)
33 {
34 	char *w = strerror(errno);
35 	fputs("rene: ", stderr);
36 	if (fmt != NULL) {
37 		va_list argp;
38 		va_start(argp, fmt);
39 		vfprintf(stderr, fmt, argp);
40 		va_end(argp);
41 	}
42 	fprintf(stderr, ": %s\n", w);
43 	exit(eval);
44 }
45 
46 int
47 strrep(char *from, char *to, char *s, char **new)
48 {
49 	char *p = strrchr(s, '/');
50 	if (p) {
51 		if (*++p == '\0')
52 			return 0;
53 	} else
54 		p = s;
55 	p = strstr(p, from);
56 	if (!p)
57 		return 0;
58 	int fromlen = strlen(from);
59 	int count = 1;
60 	if (opts & O_REPLACELAST || opts & O_REPLACEALL) {
61 		char *temp = p;
62 		while (temp) {
63 			temp = strstr(temp+fromlen, from);
64 			count = (opts & O_REPLACEALL && temp) ? count + 1 :
65 			    count;
66 			p = (opts & O_REPLACELAST && temp) ? temp : p;
67 		}
68 	}
69 
70 	if (!(*new =
71 	    malloc(strlen(s) + strlen(to)*count - fromlen*count + 1))) {
72 		warn("malloc");
73 		return 0;
74 	}
75 
76 	char *newp = *new;
77 	char *top = to;
78 	while (p) {
79 		for (; s != p; *newp++ = *s++)
80 			;
81 		for (; *top != '\0'; *newp++ = *top++)
82 			;
83 		s += fromlen;
84 		p = opts & O_REPLACEALL ? strstr(s, from) : strchr(s, '\0');
85 		p = p ? p : strchr(s, '\0');
86 		for (; s != p; *newp++ = *s++)
87 			;
88 		p = (*p == '\0') ? NULL : p;
89 		top = to;
90 	}
91 	*newp = '\0';
92 	return 1;
93 }
94 
95 int
96 ask(char *from, char *to)
97 {
98 	fprintf(stderr, "replace %s with %s? ", from, to);
99 	return getchar() == 'y';
100 }
101 
102 void
103 ren(char *from, char *to, char *f)
104 {
105 	int yes = 1;
106 	char *new = NULL;
107 	if (!strrep(from, to, f, &new))
108 		return;
109 	if ((opts & O_NOOVERRIDE || opts & O_INTERACTIVE) &&
110 	    access(new, F_OK) == 0)
111 		yes = opts & O_NOOVERRIDE ? 0 : ask(f, new);
112 	if (yes && !(opts & O_NOACT) && !(yes += rename(f, new)))
113 		warn("rename");
114 	if (opts & O_VERBOSE && yes)
115 		printf("%s -> %s\n", f, new);
116 }
117 
118 void
119 usage(void)
120 {
121 	fputs("usage: rene [-ailnov] from to file ...\n", stderr);
122 	exit(EXIT_FAILURE);
123 }
124 
125 int
126 main(int argc, char *argv[])
127 {
128 	char *from, *to;
129 
130 #ifdef __OpenBSD__
131 	if (pledge("stdio cpath rpath", NULL) == -1)
132 		err(1, "pledge");
133 #endif
134 
135 	int c;
136 	while ((c = getopt(argc, argv, "ailnov")) != -1) {
137 		switch (c) {
138 		case 'a':
139 			opts |= O_REPLACEALL;
140 			break;
141 		case 'i':
142 			opts |= O_INTERACTIVE;
143 			break;
144 		case 'l':
145 			opts |= O_REPLACELAST;
146 			break;
147 		case 'n':
148 			opts |= O_NOACT;
149 			break;
150 		case 'o':
151 			opts |= O_NOOVERRIDE;
152 			break;
153 		case 'v':
154 			opts |= O_VERBOSE;
155 			break;
156 		default:
157 			usage();
158 		}
159 	}
160 	argc -= optind;
161 	argv += optind;
162 
163 	if (argc < 3)
164 		usage();
165 	from = argv[0];
166 	to = argv[1];
167 	for (int i = 2; i < argc; i++)
168 		ren(from, to, argv[i]);
169 	return 0;
170 }