// Copyright (c) 2014 Anthony Towns // // This program is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 2 of the License, or // (at your option) any later version. #include <config.h> #include <apt-pkg/init.h> #include <apt-pkg/fileutl.h> #include <apt-pkg/error.h> #include <apt-pkg/strutl.h> #include <apt-pkg/hashes.h> #include <apt-pkg/configuration.h> #include "aptmethod.h" #include <stddef.h> #include <iostream> #include <string> #include <list> #include <vector> #include <assert.h> #include <errno.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> #include <sys/time.h> #include <apti18n.h> #define BLOCK_SIZE (512*1024) class MemBlock { char *start; size_t size; char *free; MemBlock *next; explicit MemBlock(size_t size) : size(size), next(NULL) { free = start = new char[size]; } size_t avail(void) { return size - (free - start); } public: MemBlock(void) { free = start = new char[BLOCK_SIZE]; size = BLOCK_SIZE; next = NULL; } ~MemBlock() { delete [] start; delete next; } void clear(void) { free = start; if (next) next->clear(); } char *add_easy(char *src, size_t len, char *last) { if (last) { for (MemBlock *k = this; k; k = k->next) { if (k->free == last) { if (len <= k->avail()) { char *n = k->add(src, len); assert(last == n); if (last == n) return NULL; return n; } else { break; } } else if (last >= start && last < free) { break; } } } return add(src, len); } char *add(char *src, size_t len) { if (len > avail()) { if (!next) { if (len > BLOCK_SIZE) { next = new MemBlock(len); } else { next = new MemBlock; } } return next->add(src, len); } char *dst = free; free += len; memcpy(dst, src, len); return dst; } }; struct Change { /* Ordering: * * 1. write out <offset> lines unchanged * 2. skip <del_cnt> lines from source * 3. write out <add_cnt> lines (<add>/<add_len>) */ size_t offset; size_t del_cnt; size_t add_cnt; /* lines */ size_t add_len; /* bytes */ char *add; explicit Change(size_t off) { offset = off; del_cnt = add_cnt = add_len = 0; add = NULL; } /* actually, don't write <lines> lines from <add> */ void skip_lines(size_t lines) { while (lines > 0) { char *s = (char*) memchr(add, '\n', add_len); assert(s != NULL); s++; add_len -= (s - add); add_cnt--; lines--; if (add_len == 0) { add = NULL; assert(add_cnt == 0); assert(lines == 0); } else { add = s; assert(add_cnt > 0); } } } }; class FileChanges { std::list<struct Change> changes; std::list<struct Change>::iterator where; size_t pos; // line number is as far left of iterator as possible bool pos_is_okay(void) const { #ifdef POSDEBUG size_t cpos = 0; std::list<struct Change>::const_iterator x; for (x = changes.begin(); x != where; ++x) { assert(x != changes.end()); cpos += x->offset + x->add_cnt; } return cpos == pos; #else return true; #endif } public: FileChanges() { where = changes.end(); pos = 0; } std::list<struct Change>::iterator begin(void) { return changes.begin(); } std::list<struct Change>::iterator end(void) { return changes.end(); } std::list<struct Change>::reverse_iterator rbegin(void) { return changes.rbegin(); } std::list<struct Change>::reverse_iterator rend(void) { return changes.rend(); } void add_change(Change c) { assert(pos_is_okay()); go_to_change_for(c.offset); assert(pos + where->offset == c.offset); if (c.del_cnt > 0) delete_lines(c.del_cnt); assert(pos + where->offset == c.offset); if (c.add_len > 0) { assert(pos_is_okay()); if (where->add_len > 0) new_change(); assert(where->add_len == 0 && where->add_cnt == 0); where->add_len = c.add_len; where->add_cnt = c.add_cnt; where->add = c.add; } assert(pos_is_okay()); merge(); assert(pos_is_okay()); } private: void merge(void) { while (where->offset == 0 && where != changes.begin()) { left(); } std::list<struct Change>::iterator next = where; ++next; while (next != changes.end() && next->offset == 0) { where->del_cnt += next->del_cnt; next->del_cnt = 0; if (next->add == NULL) { next = changes.erase(next); } else if (where->add == NULL) { where->add = next->add; where->add_len = next->add_len; where->add_cnt = next->add_cnt; next = changes.erase(next); } else { ++next; } } } void go_to_change_for(size_t line) { while(where != changes.end()) { if (line < pos) { left(); continue; } if (pos + where->offset + where->add_cnt <= line) { right(); continue; } // line is somewhere in this slot if (line < pos + where->offset) { break; } else if (line == pos + where->offset) { return; } else { split(line - pos); right(); return; } } /* it goes before this patch */ insert(line-pos); } void new_change(void) { insert(where->offset); } void insert(size_t offset) { assert(pos_is_okay()); assert(where == changes.end() || offset <= where->offset); if (where != changes.end()) where->offset -= offset; changes.insert(where, Change(offset)); --where; assert(pos_is_okay()); } void split(size_t offset) { assert(pos_is_okay()); assert(where->offset < offset); assert(offset < where->offset + where->add_cnt); size_t keep_lines = offset - where->offset; Change before(*where); where->del_cnt = 0; where->offset = 0; where->skip_lines(keep_lines); before.add_cnt = keep_lines; before.add_len -= where->add_len; changes.insert(where, before); --where; assert(pos_is_okay()); } void delete_lines(size_t cnt) { std::list<struct Change>::iterator x = where; assert(pos_is_okay()); while (cnt > 0) { size_t del; del = x->add_cnt; if (del > cnt) del = cnt; x->skip_lines(del); cnt -= del; ++x; if (x == changes.end()) { del = cnt; } else { del = x->offset; if (del > cnt) del = cnt; x->offset -= del; } where->del_cnt += del; cnt -= del; } assert(pos_is_okay()); } void left(void) { assert(pos_is_okay()); --where; pos -= where->offset + where->add_cnt; assert(pos_is_okay()); } void right(void) { assert(pos_is_okay()); pos += where->offset + where->add_cnt; ++where; assert(pos_is_okay()); } }; class Patch { FileChanges filechanges; MemBlock add_text; static bool retry_fwrite(char *b, size_t l, FileFd &f, Hashes * const start_hash, Hashes * const end_hash = nullptr) APT_NONNULL(1) { if (f.Write(b, l) == false) return false; if (start_hash) start_hash->Add((unsigned char*)b, l); if (end_hash) end_hash->Add((unsigned char*)b, l); return true; } static void dump_rest(FileFd &o, FileFd &i, Hashes * const start_hash, Hashes * const end_hash) { char buffer[BLOCK_SIZE]; unsigned long long l = 0; while (i.Read(buffer, sizeof(buffer), &l)) { if (l ==0 || !retry_fwrite(buffer, l, o, start_hash, end_hash)) break; } } static void dump_lines(FileFd &o, FileFd &i, size_t n, Hashes * const start_hash, Hashes * const end_hash) { char buffer[BLOCK_SIZE]; while (n > 0) { if (i.ReadLine(buffer, sizeof(buffer)) == NULL) buffer[0] = '\0'; size_t const l = strlen(buffer); if (l == 0 || buffer[l-1] == '\n') n--; retry_fwrite(buffer, l, o, start_hash, end_hash); } } static void skip_lines(FileFd &i, int n, Hashes * const start_hash) { char buffer[BLOCK_SIZE]; while (n > 0) { if (i.ReadLine(buffer, sizeof(buffer)) == NULL) buffer[0] = '\0'; size_t const l = strlen(buffer); if (l == 0 || buffer[l-1] == '\n') n--; if (start_hash) start_hash->Add((unsigned char*)buffer, l); } } static void dump_mem(FileFd &o, char *p, size_t s, Hashes *hash) APT_NONNULL(2) { retry_fwrite(p, s, o, nullptr, hash); } public: bool read_diff(FileFd &f, Hashes * const h) { char buffer[BLOCK_SIZE]; bool cmdwanted = true; Change ch(std::numeric_limits<size_t>::max()); if (f.ReadLine(buffer, sizeof(buffer)) == NULL) return _error->Error("Reading first line of patchfile %s failed", f.Name().c_str()); do { if (h != NULL) h->Add(buffer); if (cmdwanted) { char *m, *c; size_t s, e; errno = 0; s = strtoul(buffer, &m, 10); if (unlikely(m == buffer || s == std::numeric_limits<unsigned long>::max() || errno != 0)) return _error->Error("Parsing patchfile %s failed: Expected an effected line start", f.Name().c_str()); else if (*m == ',') { ++m; e = strtol(m, &c, 10); if (unlikely(m == c || e == std::numeric_limits<unsigned long>::max() || errno != 0)) return _error->Error("Parsing patchfile %s failed: Expected an effected line end", f.Name().c_str()); if (unlikely(e < s)) return _error->Error("Parsing patchfile %s failed: Effected lines end %lu is before start %lu", f.Name().c_str(), e, s); } else { e = s; c = m; } if (s > ch.offset) return _error->Error("Parsing patchfile %s failed: Effected line is after previous effected line", f.Name().c_str()); switch(*c) { case 'a': cmdwanted = false; ch.add = NULL; ch.add_cnt = 0; ch.add_len = 0; ch.offset = s; ch.del_cnt = 0; break; case 'c': if (unlikely(s == 0)) return _error->Error("Parsing patchfile %s failed: Change command can't effect line zero", f.Name().c_str()); cmdwanted = false; ch.add = NULL; ch.add_cnt = 0; ch.add_len = 0; ch.offset = s - 1; ch.del_cnt = e - s + 1; break; case 'd': if (unlikely(s == 0)) return _error->Error("Parsing patchfile %s failed: Delete command can't effect line zero", f.Name().c_str()); ch.offset = s - 1; ch.del_cnt = e - s + 1; ch.add = NULL; ch.add_cnt = 0; ch.add_len = 0; filechanges.add_change(ch); break; default: return _error->Error("Parsing patchfile %s failed: Unknown command", f.Name().c_str()); } } else { /* !cmdwanted */ if (strcmp(buffer, ".\n") == 0) { cmdwanted = true; filechanges.add_change(ch); } else { char *last = NULL; char *add; size_t l; if (ch.add) last = ch.add + ch.add_len; l = strlen(buffer); add = add_text.add_easy(buffer, l, last); if (!add) { ch.add_len += l; ch.add_cnt++; } else { if (ch.add) { filechanges.add_change(ch); ch.del_cnt = 0; } ch.offset += ch.add_cnt; ch.add = add; ch.add_len = l; ch.add_cnt = 1; } } } } while(f.ReadLine(buffer, sizeof(buffer))); return true; } void write_diff(FileFd &f) { unsigned long long line = 0; std::list<struct Change>::reverse_iterator ch; for (ch = filechanges.rbegin(); ch != filechanges.rend(); ++ch) { line += ch->offset + ch->del_cnt; } for (ch = filechanges.rbegin(); ch != filechanges.rend(); ++ch) { std::list<struct Change>::reverse_iterator mg_i, mg_e = ch; while (ch->del_cnt == 0 && ch->offset == 0) { ++ch; if (unlikely(ch == filechanges.rend())) return; } line -= ch->del_cnt; std::string buf; if (ch->add_cnt > 0) { if (ch->del_cnt == 0) { strprintf(buf, "%llua\n", line); } else if (ch->del_cnt == 1) { strprintf(buf, "%lluc\n", line+1); } else { strprintf(buf, "%llu,%lluc\n", line+1, line+ch->del_cnt); } f.Write(buf.c_str(), buf.length()); mg_i = ch; do { dump_mem(f, mg_i->add, mg_i->add_len, NULL); } while (mg_i-- != mg_e); buf = ".\n"; f.Write(buf.c_str(), buf.length()); } else if (ch->del_cnt == 1) { strprintf(buf, "%llud\n", line+1); f.Write(buf.c_str(), buf.length()); } else if (ch->del_cnt > 1) { strprintf(buf, "%llu,%llud\n", line+1, line+ch->del_cnt); f.Write(buf.c_str(), buf.length()); } line -= ch->offset; } } void apply_against_file(FileFd &out, FileFd &in, Hashes * const start_hash = nullptr, Hashes * const end_hash = nullptr) { std::list<struct Change>::iterator ch; for (ch = filechanges.begin(); ch != filechanges.end(); ++ch) { dump_lines(out, in, ch->offset, start_hash, end_hash); skip_lines(in, ch->del_cnt, start_hash); if (ch->add_len != 0) dump_mem(out, ch->add, ch->add_len, end_hash); } dump_rest(out, in, start_hash, end_hash); out.Flush(); } }; class RredMethod : public aptMethod { private: bool Debug; struct PDiffFile { std::string FileName; HashStringList ExpectedHashes; PDiffFile(std::string const &FileName, HashStringList const &ExpectedHashes) : FileName(FileName), ExpectedHashes(ExpectedHashes) {} }; HashStringList ReadExpectedHashesForPatch(unsigned int const patch, std::string const &Message) { HashStringList ExpectedHashes; for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type) { std::string tagname; strprintf(tagname, "Patch-%d-%s-Hash", patch, *type); std::string const hashsum = LookupTag(Message, tagname.c_str()); if (hashsum.empty() == false) ExpectedHashes.push_back(HashString(*type, hashsum)); } return ExpectedHashes; } protected: virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) APT_OVERRIDE { Debug = DebugEnabled(); URI Get = Itm->Uri; std::string Path = Get.Host + Get.Path; // rred:/path - no host FetchResult Res; Res.Filename = Itm->DestFile; if (Itm->Uri.empty()) { Path = Itm->DestFile; Itm->DestFile.append(".result"); } else URIStart(Res); std::vector<PDiffFile> patchfiles; Patch patch; HashStringList StartHashes; for (char const * const * type = HashString::SupportedHashes(); *type != nullptr; ++type) { std::string tagname; strprintf(tagname, "Start-%s-Hash", *type); std::string const hashsum = LookupTag(Message, tagname.c_str()); if (hashsum.empty() == false) StartHashes.push_back(HashString(*type, hashsum)); } if (FileExists(Path + ".ed") == true) { HashStringList const ExpectedHashes = ReadExpectedHashesForPatch(0, Message); std::string const FileName = Path + ".ed"; if (ExpectedHashes.usable() == false) return _error->Error("No hashes found for uncompressed patch: %s", FileName.c_str()); patchfiles.push_back(PDiffFile(FileName, ExpectedHashes)); } else { _error->PushToStack(); std::vector<std::string> patches = GetListOfFilesInDir(flNotFile(Path), "gz", true, false); _error->RevertToStack(); std::string const baseName = Path + ".ed."; unsigned int seen_patches = 0; for (std::vector<std::string>::const_iterator p = patches.begin(); p != patches.end(); ++p) { if (p->compare(0, baseName.length(), baseName) == 0) { HashStringList const ExpectedHashes = ReadExpectedHashesForPatch(seen_patches, Message); if (ExpectedHashes.usable() == false) return _error->Error("No hashes found for uncompressed patch %d: %s", seen_patches, p->c_str()); patchfiles.push_back(PDiffFile(*p, ExpectedHashes)); ++seen_patches; } } } std::string patch_name; for (std::vector<PDiffFile>::iterator I = patchfiles.begin(); I != patchfiles.end(); ++I) { patch_name = I->FileName; if (Debug == true) std::clog << "Patching " << Path << " with " << patch_name << std::endl; FileFd p; Hashes patch_hash(I->ExpectedHashes); // all patches are compressed, even if the name doesn't reflect it if (p.Open(patch_name, FileFd::ReadOnly, FileFd::Gzip) == false || patch.read_diff(p, &patch_hash) == false) { _error->DumpErrors(std::cerr, GlobalError::DEBUG, false); return false; } p.Close(); HashStringList const hsl = patch_hash.GetHashStringList(); if (hsl != I->ExpectedHashes) return _error->Error("Hash Sum mismatch for uncompressed patch %s", patch_name.c_str()); } if (Debug == true) std::clog << "Applying patches against " << Path << " and writing results to " << Itm->DestFile << std::endl; FileFd inp, out; if (inp.Open(Path, FileFd::ReadOnly, FileFd::Extension) == false) { if (Debug == true) std::clog << "FAILED to open inp " << Path << std::endl; return _error->Error("Failed to open inp %s", Path.c_str()); } if (out.Open(Itm->DestFile, FileFd::WriteOnly | FileFd::Create | FileFd::Empty | FileFd::BufferedWrite, FileFd::Extension) == false) { if (Debug == true) std::clog << "FAILED to open out " << Itm->DestFile << std::endl; return _error->Error("Failed to open out %s", Itm->DestFile.c_str()); } Hashes end_hash(Itm->ExpectedHashes); if (StartHashes.usable()) { Hashes start_hash(StartHashes); patch.apply_against_file(out, inp, &start_hash, &end_hash); if (start_hash.GetHashStringList() != StartHashes) _error->Error("The input file hadn't the expected hash!"); } else patch.apply_against_file(out, inp, nullptr, &end_hash); out.Close(); inp.Close(); if (_error->PendingError() == true) { if (Debug == true) std::clog << "FAILED to read or write files" << std::endl; return false; } if (Debug == true) { std::clog << "rred: finished file patching of " << Path << "." << std::endl; } struct stat bufbase, bufpatch; if (stat(Path.c_str(), &bufbase) != 0 || stat(patch_name.c_str(), &bufpatch) != 0) return _error->Errno("stat", _("Failed to stat %s"), Path.c_str()); struct timeval times[2]; times[0].tv_sec = bufbase.st_atime; times[1].tv_sec = bufpatch.st_mtime; times[0].tv_usec = times[1].tv_usec = 0; if (utimes(Itm->DestFile.c_str(), times) != 0) return _error->Errno("utimes",_("Failed to set modification time")); if (stat(Itm->DestFile.c_str(), &bufbase) != 0) return _error->Errno("stat", _("Failed to stat %s"), Itm->DestFile.c_str()); Res.LastModified = bufbase.st_mtime; Res.Size = bufbase.st_size; Res.TakeHashes(end_hash); URIDone(Res); return true; } public: RredMethod() : aptMethod("rred", "2.0", SendConfig), Debug(false) {} }; int main(int argc, char **argv) { int i; bool just_diff = true; bool test = false; Patch patch; if (argc <= 1) { return RredMethod().Run(); } // Usage: rred -t input output diff ... if (argc > 1 && strcmp(argv[1], "-t") == 0) { // Read config files so we see compressors. pkgInitConfig(*_config); just_diff = false; test = true; i = 4; } else if (argc > 1 && strcmp(argv[1], "-f") == 0) { just_diff = false; i = 2; } else { i = 1; } for (; i < argc; i++) { FileFd p; if (p.Open(argv[i], FileFd::ReadOnly) == false) { _error->DumpErrors(std::cerr); exit(1); } if (patch.read_diff(p, NULL) == false) { _error->DumpErrors(std::cerr); exit(2); } } if (test) { FileFd out, inp; std::cerr << "Patching " << argv[2] << " into " << argv[3] << "\n"; inp.Open(argv[2], FileFd::ReadOnly,FileFd::Extension); out.Open(argv[3], FileFd::WriteOnly | FileFd::Create | FileFd::Empty | FileFd::BufferedWrite, FileFd::Extension); patch.apply_against_file(out, inp); out.Close(); } else if (just_diff) { FileFd out; out.OpenDescriptor(STDOUT_FILENO, FileFd::WriteOnly | FileFd::Create); patch.write_diff(out); out.Close(); } else { FileFd out, inp; out.OpenDescriptor(STDOUT_FILENO, FileFd::WriteOnly | FileFd::Create | FileFd::BufferedWrite); inp.OpenDescriptor(STDIN_FILENO, FileFd::ReadOnly); patch.apply_against_file(out, inp); out.Close(); } return 0; }