diff options
| -rw-r--r-- | methods/rred.cc | 358 |
1 files changed, 187 insertions, 171 deletions
diff --git a/methods/rred.cc b/methods/rred.cc index 3d4b37e83..2d4dd768b 100644 --- a/methods/rred.cc +++ b/methods/rred.cc @@ -1,3 +1,4 @@ +// Includes /*{{{*/ #include <apt-pkg/fileutl.h> #include <apt-pkg/error.h> #include <apt-pkg/acquire-method.h> @@ -10,185 +11,205 @@ #include <stdio.h> #include <errno.h> #include <apti18n.h> - -/* this method implements a patch functionality similar to "patch --ed" that is - * used by the "tiffany" incremental packages download stuff. it differs from - * "ed" insofar that it is way more restricted (and therefore secure). in the - * moment only the "c", "a" and "d" commands of ed are implemented (diff - * doesn't output any other). additionally the records must be reverse sorted - * by line number and may not overlap (diff *seems* to produce this kind of - * output). + /*}}}*/ +/** \brief RredMethod - ed-style incremential patch method {{{ + * + * This method implements a patch functionality similar to "patch --ed" that is + * used by the "tiffany" incremental packages download stuff. It differs from + * "ed" insofar that it is way more restricted (and therefore secure). + * The currently supported ed commands are "<em>c</em>hange", "<em>a</em>dd" and + * "<em>d</em>elete" (diff doesn't output any other). + * Additionally the records must be reverse sorted by line number and + * may not overlap (diff *seems* to produce this kind of output). * */ +class RredMethod : public pkgAcqMethod { + bool Debug; + // the size of this doesn't really matter (except for performance) + const static int BUF_SIZE = 1024; + // the supported ed commands + enum Mode {MODE_CHANGED='c', MODE_DELETED='d', MODE_ADDED='a'}; + // return values + enum State {ED_OK=0, ED_ORDERING=1, ED_PARSER=2, ED_FAILURE=3}; -const char *Prog; + State applyFile(FILE *ed_cmds, FILE *in_file, FILE *out_file, + unsigned long &line, char *buffer, Hashes *hash) const; + void ignoreLineInFile(FILE *fin, char *buffer) const; + void copyLineFromFileToFile(FILE *fin, FILE *fout, + Hashes *hash, char *buffer) const; -class RredMethod : public pkgAcqMethod -{ - bool Debug; - // the size of this doesn't really matter (except for performance) - const static int BUF_SIZE = 1024; - // the ed commands - enum Mode {MODE_CHANGED, MODE_DELETED, MODE_ADDED}; - // return values - enum State {ED_OK, ED_ORDERING, ED_PARSER, ED_FAILURE}; - // this applies a single hunk, it uses a tail recursion to - // reverse the hunks in the file - int ed_rec(FILE *ed_cmds, FILE *in_file, FILE *out_file, int line, - char *buffer, unsigned int bufsize, Hashes *hash); - // apply a patch file - int ed_file(FILE *ed_cmds, FILE *in_file, FILE *out_file, Hashes *hash); + State patchFile(FILE *ed_cmds, FILE *in_file, FILE *out_file, Hashes *hash) const; protected: - // the methods main method - virtual bool Fetch(FetchItem *Itm); - - public: - - RredMethod() : pkgAcqMethod("1.1",SingleInstance | SendConfig) {}; + // the methods main method + virtual bool Fetch(FetchItem *Itm); + +public: + RredMethod() : pkgAcqMethod("1.1",SingleInstance | SendConfig) {}; }; + /*}}}*/ +/** \brief applyFile - in reverse order with a tail recursion {{{ + * + * As it is expected that the commands are in reversed order in the patch file + * we check in the first half if the command is valid, but doesn't execute it + * and move a step deeper. After reaching the end of the file we apply the + * patches in the correct order: last found command first. + * + * \param ed_cmds patch file to apply + * \param in_file base file we want to patch + * \param out_file file to write the patched result to + * \param line of command operation + * \param buffer internal used read/write buffer + * \param hash the created file for correctness + * \return the success State of the ed command executor + */ +RredMethod::State RredMethod::applyFile(FILE *ed_cmds, FILE *in_file, FILE *out_file, + unsigned long &line, char *buffer, Hashes *hash) const { + // get the current command and parse it + if (fgets(buffer, BUF_SIZE, ed_cmds) == NULL) { + if (Debug == true) + std::clog << "rred: encounter end of file - we can start patching now."; + line = 0; + return ED_OK; + } -int RredMethod::ed_rec(FILE *ed_cmds, FILE *in_file, FILE *out_file, int line, - char *buffer, unsigned int bufsize, Hashes *hash) { - int pos; - int startline; - int stopline; - int mode; - int written; - char *idx; + // parse in the effected linenumbers + char* idx; + errno=0; + unsigned long const startline = strtol(buffer, &idx, 10); + if (errno == ERANGE || errno == EINVAL) { + _error->Errno("rred", "startline is an invalid number"); + return ED_PARSER; + } + if (startline > line) { + _error->Error("rred: The start line (%lu) of the next command is higher than the last line (%lu). This is not allowed.", startline, line); + return ED_ORDERING; + } + unsigned long stopline; + if (*idx == ',') { + idx++; + errno=0; + stopline = strtol(idx, &idx, 10); + if (errno == ERANGE || errno == EINVAL) { + _error->Errno("rred", "stopline is an invalid number"); + return ED_PARSER; + } + } + else { + stopline = startline; + } + line = startline; - /* get the current command and parse it*/ - if (fgets(buffer, bufsize, ed_cmds) == NULL) { - return line; - } - startline = strtol(buffer, &idx, 10); - if (startline < line) { - return ED_ORDERING; - } - if (*idx == ',') { - idx++; - stopline = strtol(idx, &idx, 10); - } - else { - stopline = startline; - } - if (*idx == 'c') { - mode = MODE_CHANGED; - if (Debug == true) { - std::clog << "changing from line " << startline - << " to " << stopline << std::endl; - } - } - else if (*idx == 'a') { - mode = MODE_ADDED; - if (Debug == true) { - std::clog << "adding after line " << startline << std::endl; - } - } - else if (*idx == 'd') { - mode = MODE_DELETED; - if (Debug == true) { - std::clog << "deleting from line " << startline - << " to " << stopline << std::endl; - } - } - else { - return ED_PARSER; - } - /* get the current position */ - pos = ftell(ed_cmds); - /* if this is add or change then go to the next full stop */ - if ((mode == MODE_CHANGED) || (mode == MODE_ADDED)) { - do { - fgets(buffer, bufsize, ed_cmds); - while ((strlen(buffer) == (bufsize - 1)) - && (buffer[bufsize - 2] != '\n')) { - fgets(buffer, bufsize, ed_cmds); - buffer[0] = ' '; - } - } while (strncmp(buffer, ".", 1) != 0); - } - /* do the recursive call */ - line = ed_rec(ed_cmds, in_file, out_file, line, buffer, bufsize, - hash); - /* pass on errors */ - if (line < 0) { - return line; - } - /* apply our hunk */ - fseek(ed_cmds, pos, SEEK_SET); - /* first wind to the current position */ - if (mode != MODE_ADDED) { - startline -= 1; - } - while (line < startline) { - fgets(buffer, bufsize, in_file); - written = fwrite(buffer, 1, strlen(buffer), out_file); - hash->Add((unsigned char*)buffer, written); - while ((strlen(buffer) == (bufsize - 1)) - && (buffer[bufsize - 2] != '\n')) { - fgets(buffer, bufsize, in_file); - written = fwrite(buffer, 1, strlen(buffer), out_file); - hash->Add((unsigned char*)buffer, written); - } - line++; - } - /* include from ed script */ - if ((mode == MODE_ADDED) || (mode == MODE_CHANGED)) { - do { - fgets(buffer, bufsize, ed_cmds); - if (strncmp(buffer, ".", 1) != 0) { - written = fwrite(buffer, 1, strlen(buffer), out_file); - hash->Add((unsigned char*)buffer, written); - while ((strlen(buffer) == (bufsize - 1)) - && (buffer[bufsize - 2] != '\n')) { - fgets(buffer, bufsize, ed_cmds); - written = fwrite(buffer, 1, strlen(buffer), out_file); - hash->Add((unsigned char*)buffer, written); - } - } - else { - break; - } - } while (1); - } - /* ignore the corresponding number of lines from input */ - if ((mode == MODE_DELETED) || (mode == MODE_CHANGED)) { - while (line < stopline) { - fgets(buffer, bufsize, in_file); - while ((strlen(buffer) == (bufsize - 1)) - && (buffer[bufsize - 2] != '\n')) { - fgets(buffer, bufsize, in_file); - } - line++; - } - } - return line; -} + // which command to execute on this line(s)? + switch (*idx) { + case MODE_CHANGED: + if (Debug == true) + std::clog << "Change from line " << startline << " to " << stopline << std::endl; + break; + case MODE_ADDED: + if (Debug == true) + std::clog << "Insert after line " << startline << std::endl; + break; + case MODE_DELETED: + if (Debug == true) + std::clog << "Delete from line " << startline << " to " << stopline << std::endl; + break; + default: + _error->Error("rred: Unknown ed command '%c'. Abort.", *idx); + return ED_PARSER; + } + unsigned char mode = *idx; + + // save the current position + unsigned const long pos = ftell(ed_cmds); + + // if this is add or change then go to the next full stop + if (mode == MODE_CHANGED || mode == MODE_ADDED) { + do + ignoreLineInFile(ed_cmds, buffer); + while (strncmp(buffer, ".", 1) != 0); + } + + // do the recursive call - the last command is the one we need to execute at first + const State child = applyFile(ed_cmds, in_file, out_file, line, buffer, hash); + if (child != ED_OK) { + return child; + } + + // change and delete are working on "line" - add is done after "line" + if (mode != MODE_ADDED) + line++; + + // first wind to the current position and copy over all unchanged lines + while (line < startline) { + fgets(buffer, BUF_SIZE, in_file); + copyLineFromFileToFile(in_file, out_file, hash, buffer); + line++; + } + + if (mode != MODE_ADDED) + line--; -int RredMethod::ed_file(FILE *ed_cmds, FILE *in_file, FILE *out_file, - Hashes *hash) { + // include data from ed script + if (mode == MODE_CHANGED || mode == MODE_ADDED) { + fseek(ed_cmds, pos, SEEK_SET); + while(fgets(buffer, BUF_SIZE, ed_cmds) != NULL) { + if (strncmp(buffer, ".", 1) != 0) + copyLineFromFileToFile(ed_cmds, out_file, hash, buffer); + else + break; + } + } + + // ignore the corresponding number of lines from input + if (mode == MODE_CHANGED || mode == MODE_DELETED) { + while (line < stopline) { + ignoreLineInFile(in_file, buffer); + line++; + } + } + return ED_OK; +} + /*}}}*/ +void RredMethod::copyLineFromFileToFile(FILE *fin, FILE *fout, /*{{{*/ + Hashes *hash, char *buffer) const { + size_t written = fwrite(buffer, 1, strlen(buffer), fout); + hash->Add((unsigned char*)buffer, written); + while (strlen(buffer) == (BUF_SIZE - 1) && + buffer[BUF_SIZE - 2] != '\n') { + fgets(buffer, BUF_SIZE, fin); + written = fwrite(buffer, 1, strlen(buffer), fout); + hash->Add((unsigned char*)buffer, written); + } +} + /*}}}*/ +void RredMethod::ignoreLineInFile(FILE *fin, char *buffer) const { /*{{{*/ + fgets(buffer, BUF_SIZE, fin); + while (strlen(buffer) == (BUF_SIZE - 1) && + buffer[BUF_SIZE - 2] != '\n') { + fgets(buffer, BUF_SIZE, fin); + buffer[0] = ' '; + } +} + /*}}}*/ +RredMethod::State RredMethod::patchFile(FILE *ed_cmds, FILE *in_file, FILE *out_file, /*{{{*/ + Hashes *hash) const { char buffer[BUF_SIZE]; - int result; - int written; /* we do a tail recursion to read the commands in the right order */ - result = ed_rec(ed_cmds, in_file, out_file, 0, buffer, BUF_SIZE, - hash); + unsigned long line = -1; // assign highest possible value + State result = applyFile(ed_cmds, in_file, out_file, line, buffer, hash); /* read the rest from infile */ - if (result >= 0) { + if (result == ED_OK) { while (fgets(buffer, BUF_SIZE, in_file) != NULL) { - written = fwrite(buffer, 1, strlen(buffer), out_file); + size_t const written = fwrite(buffer, 1, strlen(buffer), out_file); hash->Add((unsigned char*)buffer, written); } } - else { - return ED_FAILURE; - } - return ED_OK; + return result; } - -bool RredMethod::Fetch(FetchItem *Itm) + /*}}}*/ +bool RredMethod::Fetch(FetchItem *Itm) /*{{{*/ { Debug = _config->FindB("Debug::pkgAcquire::RRed", false); URI Get = Itm->Uri; @@ -219,7 +240,7 @@ bool RredMethod::Fetch(FetchItem *Itm) FILE* fPatch = fdopen(Patch.Fd(), "r"); FILE* fTo = fdopen(To.Fd(), "w"); // now do the actual patching - if (ed_file(fPatch, fFrom, fTo, &Hash) != ED_OK) { + if (patchFile(fPatch, fFrom, fTo, &Hash) != ED_OK) { _error->Errno("rred", _("Could not patch file")); return false; } @@ -256,10 +277,8 @@ bool RredMethod::Fetch(FetchItem *Itm) return true; } - -/** - * \brief Wrapper class for testing rred - */ + /*}}}*/ +/** \brief Wrapper class for testing rred */ /*{{{*/ class TestRredMethod : public RredMethod { public: /** \brief Run rred in debug test mode @@ -276,9 +295,8 @@ public: return Fetch(test); } }; - -/** - * \brief Starter for the rred method (or its test method) + /*}}}*/ +/** \brief Starter for the rred method (or its test method) {{{ * * Used without parameters is the normal behavior for methods for * the APT acquire system. While this works great for the acquire system @@ -289,9 +307,6 @@ public: * and will write the result to "Testfile.result". */ int main(int argc, char *argv[]) { - Prog = strrchr(argv[0],'/'); - Prog++; - if (argc == 0) { RredMethod Mth; return Mth.Run(); @@ -302,3 +317,4 @@ int main(int argc, char *argv[]) { return result; } } + /*}}}*/ |