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[apt.git] / methods / store.cc
1 // -*- mode: cpp; mode: fold -*-
2 // Description /*{{{*/
3 /* ######################################################################
4
5 Store method - Takes a file URI and stores its content (for which it will
6 calculate the hashes) in the given destination. The input file will be
7 extracted based on its file extension (or with the given compressor if
8 called with one of the compatible symlinks) and potentially recompressed
9 based on the file extension of the destination filename.
10
11 ##################################################################### */
12 /*}}}*/
13 // Include Files /*{{{*/
14 #include <config.h>
15
16 #include <apt-pkg/configuration.h>
17 #include <apt-pkg/error.h>
18 #include <apt-pkg/fileutl.h>
19 #include <apt-pkg/hashes.h>
20 #include <apt-pkg/strutl.h>
21 #include <apt-pkg/aptconfiguration.h>
22 #include "aptmethod.h"
23
24 #include <string.h>
25 #include <sys/stat.h>
26 #include <sys/time.h>
27 #include <string>
28 #include <vector>
29
30 #include <apti18n.h>
31 /*}}}*/
32
33 class StoreMethod : public aptMethod
34 {
35 std::string const Prog;
36 virtual bool Fetch(FetchItem *Itm) APT_OVERRIDE;
37
38 public:
39
40 explicit StoreMethod(std::string const &pProg) : aptMethod(pProg.c_str(),"1.2",SingleInstance | SendConfig), Prog(pProg) {};
41 };
42
43 static bool OpenFileWithCompressorByName(FileFd &fileFd, std::string const &Filename, unsigned int const Mode, std::string const &Name)
44 {
45 if (Name == "store")
46 return fileFd.Open(Filename, Mode, FileFd::Extension);
47
48 std::vector<APT::Configuration::Compressor> const compressors = APT::Configuration::getCompressors();
49 std::vector<APT::Configuration::Compressor>::const_iterator compressor = compressors.begin();
50 for (; compressor != compressors.end(); ++compressor)
51 if (compressor->Name == Name)
52 break;
53 if (compressor == compressors.end())
54 return _error->Error("Extraction of file %s requires unknown compressor %s", Filename.c_str(), Name.c_str());
55 return fileFd.Open(Filename, Mode, *compressor);
56 }
57
58
59 /*}}}*/
60 bool StoreMethod::Fetch(FetchItem *Itm) /*{{{*/
61 {
62 URI Get = Itm->Uri;
63 std::string Path = Get.Host + Get.Path; // To account for relative paths
64
65 FetchResult Res;
66 Res.Filename = Itm->DestFile;
67 URIStart(Res);
68
69 // Open the source and destination files
70 FileFd From;
71 if (_config->FindB("Method::Compress", false) == false)
72 {
73 if (OpenFileWithCompressorByName(From, Path, FileFd::ReadOnly, Prog) == false)
74 return false;
75 if(From.IsCompressed() && From.FileSize() == 0)
76 return _error->Error(_("Empty files can't be valid archives"));
77 }
78 else
79 From.Open(Path, FileFd::ReadOnly, FileFd::Extension);
80 if (From.IsOpen() == false || From.Failed() == true)
81 return false;
82
83 FileFd To;
84 if (Itm->DestFile != "/dev/null" && Itm->DestFile != Path)
85 {
86 if (_config->FindB("Method::Compress", false) == false)
87 To.Open(Itm->DestFile, FileFd::WriteOnly | FileFd::Create | FileFd::Atomic, FileFd::Extension);
88 else if (OpenFileWithCompressorByName(To, Itm->DestFile, FileFd::WriteOnly | FileFd::Create | FileFd::Empty, Prog) == false)
89 return false;
90
91 if (To.IsOpen() == false || To.Failed() == true)
92 return false;
93 To.EraseOnFailure();
94 }
95
96 // Read data from source, generate checksums and write
97 Hashes Hash(Itm->ExpectedHashes);
98 bool Failed = false;
99 Res.Size = 0;
100 while (1)
101 {
102 unsigned char Buffer[4*1024];
103 unsigned long long Count = 0;
104
105 if (!From.Read(Buffer,sizeof(Buffer),&Count))
106 {
107 if (To.IsOpen())
108 To.OpFail();
109 return false;
110 }
111 if (Count == 0)
112 break;
113 Res.Size += Count;
114
115 Hash.Add(Buffer,Count);
116 if (To.IsOpen() && To.Write(Buffer,Count) == false)
117 {
118 Failed = true;
119 break;
120 }
121 }
122
123 From.Close();
124 To.Close();
125
126 if (Failed == true)
127 return false;
128
129 if (TransferModificationTimes(Path.c_str(), Itm->DestFile.c_str(), Res.LastModified) == false)
130 return false;
131
132 // Return a Done response
133 Res.TakeHashes(Hash);
134
135 URIDone(Res);
136 return true;
137 }
138 /*}}}*/
139
140 int main(int, char *argv[])
141 {
142 return StoreMethod(flNotDir(argv[0])).Run();
143 }