1 /*
2 * lftp - file transfer program
3 *
4 * Copyright (c) 1996-2013 by Alexander V. Lukyanov (lav@yars.free.net)
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include <config.h>
21 #include <sys/types.h>
22 #include <sys/stat.h>
23 #include <fcntl.h>
24 #include <unistd.h>
25 #include <stddef.h>
26 #include "trio.h"
27 #include "History.h"
28 #include "url.h"
29 #include "misc.h"
30
31 #define super KeyValueDB
32
History()33 History::History()
34 {
35 full=0;
36 stamp=0;
37 fd=-1;
38 modified=false;
39 const char *home=get_lftp_data_dir();
40 if(home)
41 file.vset(home,"/cwd_history",NULL);
42 }
43
~History()44 History::~History()
45 {
46 Close();
47 if(full)
48 delete full;
49 }
50
extract_url(const char * res)51 const char *History::extract_url(const char *res)
52 {
53 const char *url=strchr(res,':');
54 if(url)
55 url++;
56 else
57 url=res;
58
59 if(url::is_url(url))
60 return url;
61
62 return url::decode(url);
63 }
64
extract_stamp(const char * res)65 time_t History::extract_stamp(const char *res)
66 {
67 return atol(res);
68 }
69
Lookup(const FileAccess * s)70 const char *History::Lookup(const FileAccess *s)
71 {
72 const char *url=s->GetConnectURL(s->NO_PATH|s->NO_PASSWORD);
73 if(!url)
74 return 0;
75 const char *res=super::Lookup(url);
76 if(res)
77 return extract_url(res);
78 Refresh();
79 Close();
80 if(!full)
81 return 0;
82 res=full->Lookup(url);
83 if(res)
84 return extract_url(res);
85 return 0;
86 }
87
Refresh()88 void History::Refresh()
89 {
90 if(!file)
91 return;
92 struct stat st;
93 if((fd==-1 ? stat(file,&st) : fstat(fd,&st)) == -1)
94 return;
95 if(st.st_mtime==stamp)
96 return;
97 Load();
98 }
99
Load()100 void History::Load()
101 {
102 if(full)
103 full->Empty();
104 if(!file)
105 return;
106 if(fd==-1)
107 {
108 fd=open(file,O_RDONLY);
109 if(fd==-1)
110 return;
111 fcntl(fd,F_SETFD,FD_CLOEXEC);
112 if(Lock(fd,F_RDLCK)==-1)
113 fprintf(stderr,"%s: lock for reading failed, trying to read anyway\n",file.get());
114 }
115 if(!full)
116 full=new KeyValueDB;
117 struct stat st;
118 fstat(fd,&st);
119 stamp=st.st_mtime;
120 lseek(fd,0,SEEK_SET);
121
122 full->Read(dup(fd)); // Read closes fd
123 }
124
Close()125 void History::Close()
126 {
127 if(fd!=-1)
128 {
129 close(fd);
130 fd=-1;
131 }
132 }
133
Set(const FileAccess * s,const FileAccess::Path & cwd)134 void History::Set(const FileAccess *s,const FileAccess::Path &cwd)
135 {
136 if(cwd.path==0 || !strcmp(cwd.path,"~") || s->GetHostName()==0)
137 return;
138 xstring res;
139 res.setf("%lu:",(unsigned long)time(0));
140 if(!cwd.url)
141 {
142 res.append_url_encoded(cwd,URL_PATH_UNSAFE);
143 if(!cwd.is_file && url::dir_needs_trailing_slash(s->GetProto()) && res.last_char()!='/')
144 res.append('/');
145 }
146 else
147 res.append(cwd.url);
148 super::Add(s->GetConnectURL(s->NO_PATH|s->NO_PASSWORD),res);
149 modified=true;
150 }
151
Save()152 void History::Save()
153 {
154 Close();
155 if(!file)
156 return;
157 if(!modified)
158 return;
159 fd=open(file,O_RDWR|O_CREAT,0600);
160 if(fd==-1)
161 return;
162 fcntl(fd,F_SETFD,FD_CLOEXEC);
163 if(Lock(fd,F_WRLCK)==-1)
164 {
165 fprintf(stderr,"%s: lock for writing failed\n",file.get());
166 Close();
167 return;
168 }
169 Refresh();
170
171 // merge
172 int count=0;
173 for(Pair *p=chain; p; p=p->next)
174 {
175 time_t new_stamp=extract_stamp(p->value);
176 time_t old_stamp=0;
177 const char *old_value=full->Lookup(p->key);
178 if(old_value)
179 old_stamp=extract_stamp(old_value);
180 if(old_stamp<new_stamp)
181 {
182 full->Add(p->key,p->value);
183 count++;
184 }
185 }
186
187 if(count==0)
188 {
189 Close();
190 return;
191 }
192
193 lseek(fd,0,SEEK_SET);
194
195 #ifdef HAVE_FTRUNCATE
196 if(ftruncate(fd,0)==-1) // note the following statement
197 #endif
198 close(open(file,O_WRONLY|O_TRUNC));
199
200 full->Write(fd);
201 fd=-1; // Write closes file
202 }
203