[apt.git] / methods / rred.cc

// 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/fileutl.h>
#include <apt-pkg/mmap.h>
#include <apt-pkg/error.h>
#include <apt-pkg/acquire-method.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/hashes.h>
#include <apt-pkg/configuration.h>

#include <string>
#include <list>
#include <vector>
#include <iterator>

#include <fcntl.h>
#include <assert.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;
   struct MemBlock *next;

   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;

   Change(int 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)
   {
#ifdef POSDEBUG
      size_t cpos = 0;
      std::list<struct Change>::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, FILE *f, Hashes *hash)
   {
      size_t r = 1;
      while (r > 0 && l > 0)
      {
         r = fwrite(b, 1, l, f);
	 if (hash)
	    hash->Add((unsigned char*)b, r);
	 l -= r;
	 b += r;
      }
      return l == 0;
   }

   static void dump_rest(FILE *o, FILE *i, Hashes *hash)
   {
      char buffer[BLOCK_SIZE];
      size_t l;
      while (0 < (l = fread(buffer, 1, sizeof(buffer), i))) {
	 if (!retry_fwrite(buffer, l, o, hash))
	    break;
      }
   }

   static void dump_lines(FILE *o, FILE *i, size_t n, Hashes *hash)
   {
      char buffer[BLOCK_SIZE];
      while (n > 0) {
	 if (fgets(buffer, sizeof(buffer), i) == 0)
	    buffer[0] = '\0';
	 size_t const l = strlen(buffer);
	 if (l == 0 || buffer[l-1] == '\n')
	    n--;
	 retry_fwrite(buffer, l, o, hash);
      }
   }

   static void skip_lines(FILE *i, int n)
   {
      char buffer[BLOCK_SIZE];
      while (n > 0) {
	 if (fgets(buffer, sizeof(buffer), i) == 0)
	    buffer[0] = '\0';
	 size_t const l = strlen(buffer);
	 if (l == 0 || buffer[l-1] == '\n')
	    n--;
      }
   }

   static void dump_mem(FILE *o, char *p, size_t s, Hashes *hash) {
      retry_fwrite(p, s, o, hash);
   }

   public:

   void read_diff(FileFd &f)
   {
      char buffer[BLOCK_SIZE];
      bool cmdwanted = true;

      Change ch(0);
      while(f.ReadLine(buffer, sizeof(buffer)))
      {
	 if (cmdwanted) {
	    char *m, *c;
	    size_t s, e;
	    s = strtol(buffer, &m, 10);
	    if (m == buffer) {
	       s = e = ch.offset + ch.add_cnt;
	       c = buffer;
	    } else if (*m == ',') {
	       m++;
	       e = strtol(m, &c, 10);
	    } else {
	       e = s;
	       c = m;
	    }
	    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':
		  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':
		  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;
	    }
	 } else { /* !cmdwanted */
	    if (buffer[0] == '.' && buffer[1] == '\n') {
	       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;
	       }
	    }
	 }
      }
   }

   void write_diff(FILE *f)
   {
      size_t 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;
	 line -= ch->del_cnt;
	 if (ch->add_cnt > 0) {
	    if (ch->del_cnt == 0) {
	       fprintf(f, "%lua\n", line);
	    } else if (ch->del_cnt == 1) {
	       fprintf(f, "%luc\n", line+1);
	    } else {
	       fprintf(f, "%lu,%luc\n", line+1, line+ch->del_cnt);
	    }

	    mg_i = ch;
	    do {
	       dump_mem(f, mg_i->add, mg_i->add_len, NULL);
	    } while (mg_i-- != mg_e);

	    fprintf(f, ".\n");
	 } else if (ch->del_cnt == 1) {
	    fprintf(f, "%lud\n", line+1);
	 } else if (ch->del_cnt > 1) {
	    fprintf(f, "%lu,%lud\n", line+1, line+ch->del_cnt);
	 }
	 line -= ch->offset;
      }
   }

   void apply_against_file(FILE *out, FILE *in, Hashes *hash = NULL)
   {
      std::list<struct Change>::iterator ch;
      for (ch = filechanges.begin(); ch != filechanges.end(); ++ch) {
	 dump_lines(out, in, ch->offset, hash);
	 skip_lines(in, ch->del_cnt);
	 dump_mem(out, ch->add, ch->add_len, hash);
      }
      dump_rest(out, in, hash);
   }
};

class RredMethod : public pkgAcqMethod {
   private:
      bool Debug;

   protected:
      virtual bool Fetch(FetchItem *Itm) {
	 Debug = _config->FindB("Debug::pkgAcquire::RRed", false);
	 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<std::string> patchpaths;
	 Patch patch;

	 if (FileExists(Path + ".ed") == true)
	    patchpaths.push_back(Path + ".ed");
	 else
	 {
	    _error->PushToStack();
	    std::vector<std::string> patches = GetListOfFilesInDir(flNotFile(Path), "gz", true, false);
	    _error->RevertToStack();

	    std::string const baseName = Path + ".ed.";
	    for (std::vector<std::string>::const_iterator p = patches.begin();
		  p != patches.end(); ++p)
	       if (p->compare(0, baseName.length(), baseName) == 0)
		  patchpaths.push_back(*p);
	 }

	 std::string patch_name;
	 for (std::vector<std::string>::iterator I = patchpaths.begin();
	       I != patchpaths.end();
	       ++I)
	 {
	    patch_name = *I;
	    if (Debug == true)
	       std::clog << "Patching " << Path << " with " << patch_name
		  << std::endl;

	    FileFd p;
	    // all patches are compressed, even if the name doesn't reflect it
	    if (p.Open(patch_name, FileFd::ReadOnly, FileFd::Gzip) == false) {
	       std::cerr << "Could not open patch file " << patch_name << std::endl;
	       _error->DumpErrors(std::cerr);
	       abort();
	    }
	    patch.read_diff(p);
	    p.Close();
	 }

	 if (Debug == true)
	    std::clog << "Applying patches against " << Path
	       << " and writing results to " << Itm->DestFile
	       << std::endl;

	 FILE *inp = fopen(Path.c_str(), "r");
	 FILE *out = fopen(Itm->DestFile.c_str(), "w");

	 Hashes hash;

	 patch.apply_against_file(out, inp, &hash);

	 fclose(out);
	 fclose(inp);

	 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"));

	 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"));

	 Res.LastModified = bufbase.st_mtime;
	 Res.Size = bufbase.st_size;
	 Res.TakeHashes(hash);
	 URIDone(Res);

	 return true;
      }

   public:
      RredMethod() : pkgAcqMethod("2.0",SingleInstance | SendConfig), Debug(false) {}
};

int main(int argc, char **argv)
{
   int i;
   bool just_diff = true;
   Patch patch;

   if (argc <= 1) {
      RredMethod Mth;
      return Mth.Run();
   }

   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);
      }
      patch.read_diff(p);
   }

   if (just_diff) {
      patch.write_diff(stdout);
   } else {
      FILE *out, *inp;
      out = stdout;
      inp = stdin;

      patch.apply_against_file(out, inp);
   }
   return 0;
}
Commit	Line	Data
dbd5418b AT	1	// Copyright (c) 2014 Anthony Towns
	2	//
	3	// This program is free software; you can redistribute it and/or modify
	4	// it under the terms of the GNU General Public License as published by
	5	// the Free Software Foundation; either version 2 of the License, or
	6	// (at your option) any later version.
	7
ea542140 DK	8	#include <config.h>
ea542140 DK	9
2e178d1c	10	#include <apt-pkg/fileutl.h>
bb1293d9	11	#include <apt-pkg/mmap.h>
2e178d1c MV	12	#include <apt-pkg/error.h>
	13	#include <apt-pkg/acquire-method.h>
	14	#include <apt-pkg/strutl.h>
	15	#include <apt-pkg/hashes.h>
472ff00e	16	#include <apt-pkg/configuration.h>
2e178d1c	17
dbd5418b AT	18	#include <string>
	19	#include <list>
	20	#include <vector>
	21	#include <iterator>
	22
25d99f3b	23	#include <fcntl.h>
dbd5418b AT	24	#include <assert.h>
	25	#include <stdio.h>
	26	#include <stdlib.h>
	27	#include <string.h>
2e178d1c	28	#include <sys/stat.h>
246bbb61	29	#include <sys/time.h>
dbd5418b	30
2e178d1c	31	#include <apti18n.h>
dbd5418b AT	32
	33	#define BLOCK_SIZE (512*1024)
	34
	35	class MemBlock {
	36	char *start;
	37	size_t size;
	38	char *free;
	39	struct MemBlock *next;
	40
25d99f3b	41	MemBlock(size_t size) : size(size), next(NULL)
dbd5418b AT	42	{
dbd5418b AT	43	free = start = new char[size];
dbd5418b AT	44	}
	45
	46	size_t avail(void) { return size - (free - start); }
	47
	48	public:
	49
	50	MemBlock(void) {
	51	free = start = new char[BLOCK_SIZE];
	52	size = BLOCK_SIZE;
	53	next = NULL;
	54	}
	55
	56	~MemBlock() {
	57	delete [] start;
	58	delete next;
	59	}
	60
	61	void clear(void) {
	62	free = start;
	63	if (next)
	64	next->clear();
	65	}
	66
	67	char add_easy(char src, size_t len, char *last)
	68	{
	69	if (last) {
	70	for (MemBlock *k = this; k; k = k->next) {
	71	if (k->free == last) {
	72	if (len <= k->avail()) {
	73	char *n = k->add(src, len);
	74	assert(last == n);
	75	if (last == n)
	76	return NULL;
	77	return n;
	78	} else {
	79	break;
	80	}
	81	} else if (last >= start && last < free) {
	82	break;
	83	}
	84	}
	85	}
	86	return add(src, len);
	87	}
	88
	89	char add(char src, size_t len) {
	90	if (len > avail()) {
	91	if (!next) {
	92	if (len > BLOCK_SIZE) {
	93	next = new MemBlock(len);
	94	} else {
	95	next = new MemBlock;
	96	}
	97	}
	98	return next->add(src, len);
	99	}
	100	char *dst = free;
	101	free += len;
	102	memcpy(dst, src, len);
	103	return dst;
	104	}
2e178d1c	105	};
dbd5418b AT	106
	107	struct Change {
	108	/* Ordering:
	109	*
	110	* 1. write out <offset> lines unchanged
	111	* 2. skip <del_cnt> lines from source
	112	* 3. write out <add_cnt> lines (<add>/<add_len>)
	113	*/
	114	size_t offset;
	115	size_t del_cnt;
	116	size_t add_cnt; /* lines */
	117	size_t add_len; /* bytes */
	118	char *add;
	119
	120	Change(int off)
	121	{
	122	offset = off;
	123	del_cnt = add_cnt = add_len = 0;
	124	add = NULL;
	125	}
	126
	127	/* actually, don't write <lines> lines from <add> */
	128	void skip_lines(size_t lines)
	129	{
	130	while (lines > 0) {
	131	char s = (char) memchr(add, '\n', add_len);
	132	assert(s != NULL);
	133	s++;
	134	add_len -= (s - add);
	135	add_cnt--;
	136	lines--;
	137	if (add_len == 0) {
	138	add = NULL;
	139	assert(add_cnt == 0);
	140	assert(lines == 0);
	141	} else {
	142	add = s;
	143	assert(add_cnt > 0);
	144	}
d84cd865 MV	145	}
d84cd865 MV	146	}
bb1293d9	147	};
dbd5418b AT	148
	149	class FileChanges {
	150	std::list<struct Change> changes;
	151	std::list<struct Change>::iterator where;
	152	size_t pos; // line number is as far left of iterator as possible
	153
	154	bool pos_is_okay(void)
	155	{
	156	#ifdef POSDEBUG
	157	size_t cpos = 0;
	158	std::list<struct Change>::iterator x;
25d99f3b	159	for (x = changes.begin(); x != where; ++x) {
dbd5418b AT	160	assert(x != changes.end());
	161	cpos += x->offset + x->add_cnt;
	162	}
	163	return cpos == pos;
bb1293d9	164	#else
dbd5418b	165	return true;
bb1293d9	166	#endif
dbd5418b AT	167	}
	168
	169	public:
	170	FileChanges() {
	171	where = changes.end();
	172	pos = 0;
	173	}
	174
	175	std::list<struct Change>::iterator begin(void) { return changes.begin(); }
	176	std::list<struct Change>::iterator end(void) { return changes.end(); }
	177
	178	std::list<struct Change>::reverse_iterator rbegin(void) { return changes.rbegin(); }
	179	std::list<struct Change>::reverse_iterator rend(void) { return changes.rend(); }
	180
	181	void add_change(Change c) {
	182	assert(pos_is_okay());
	183	go_to_change_for(c.offset);
	184	assert(pos + where->offset == c.offset);
	185	if (c.del_cnt > 0)
	186	delete_lines(c.del_cnt);
	187	assert(pos + where->offset == c.offset);
	188	if (c.add_len > 0) {
	189	assert(pos_is_okay());
	190	if (where->add_len > 0)
	191	new_change();
	192	assert(where->add_len == 0 && where->add_cnt == 0);
	193
	194	where->add_len = c.add_len;
	195	where->add_cnt = c.add_cnt;
	196	where->add = c.add;
	197	}
	198	assert(pos_is_okay());
	199	merge();
	200	assert(pos_is_okay());
	201	}
	202
	203	private:
	204	void merge(void)
	205	{
	206	while (where->offset == 0 && where != changes.begin()) {
	207	left();
	208	}
	209	std::list<struct Change>::iterator next = where;
25d99f3b	210	++next;
dbd5418b AT	211
	212	while (next != changes.end() && next->offset == 0) {
	213	where->del_cnt += next->del_cnt;
	214	next->del_cnt = 0;
	215	if (next->add == NULL) {
	216	next = changes.erase(next);
	217	} else if (where->add == NULL) {
	218	where->add = next->add;
	219	where->add_len = next->add_len;
	220	where->add_cnt = next->add_cnt;
	221	next = changes.erase(next);
	222	} else {
25d99f3b	223	++next;
dbd5418b AT	224	}
	225	}
	226	}
	227
	228	void go_to_change_for(size_t line)
47d2bc78	229	{
dbd5418b AT	230	while(where != changes.end()) {
	231	if (line < pos) {
	232	left();
	233	continue;
	234	}
	235	if (pos + where->offset + where->add_cnt <= line) {
	236	right();
	237	continue;
	238	}
	239	// line is somewhere in this slot
	240	if (line < pos + where->offset) {
	241	break;
	242	} else if (line == pos + where->offset) {
	243	return;
	244	} else {
	245	split(line - pos);
	246	right();
	247	return;
47d2bc78	248	}
bb1293d9	249	}
dbd5418b AT	250	/* it goes before this patch */
	251	insert(line-pos);
	252	}
	253
	254	void new_change(void) { insert(where->offset); }
	255
	256	void insert(size_t offset)
	257	{
	258	assert(pos_is_okay());
	259	assert(where == changes.end() \|\| offset <= where->offset);
	260	if (where != changes.end())
	261	where->offset -= offset;
	262	changes.insert(where, Change(offset));
25d99f3b	263	--where;
dbd5418b AT	264	assert(pos_is_okay());
	265	}
	266
	267	void split(size_t offset)
	268	{
	269	assert(pos_is_okay());
	270
	271	assert(where->offset < offset);
	272	assert(offset < where->offset + where->add_cnt);
	273
	274	size_t keep_lines = offset - where->offset;
	275
	276	Change before(*where);
47d2bc78	277
dbd5418b AT	278	where->del_cnt = 0;
	279	where->offset = 0;
	280	where->skip_lines(keep_lines);
	281
	282	before.add_cnt = keep_lines;
	283	before.add_len -= where->add_len;
	284
	285	changes.insert(where, before);
25d99f3b	286	--where;
dbd5418b	287	assert(pos_is_okay());
3de9ff77	288	}
dbd5418b	289
dbd5418b AT	290	void delete_lines(size_t cnt)
	291	{
	292	std::list<struct Change>::iterator x = where;
	293	assert(pos_is_okay());
	294	while (cnt > 0)
	295	{
	296	size_t del;
	297	del = x->add_cnt;
	298	if (del > cnt)
	299	del = cnt;
	300	x->skip_lines(del);
	301	cnt -= del;
	302
25d99f3b	303	++x;
dbd5418b AT	304	if (x == changes.end()) {
	305	del = cnt;
	306	} else {
	307	del = x->offset;
	308	if (del > cnt)
	309	del = cnt;
	310	x->offset -= del;
	311	}
	312	where->del_cnt += del;
	313	cnt -= del;
	314	}
	315	assert(pos_is_okay());
	316	}
47d2bc78	317
dbd5418b AT	318	void left(void) {
dbd5418b AT	319	assert(pos_is_okay());
25d99f3b	320	--where;
dbd5418b AT	321	pos -= where->offset + where->add_cnt;
	322	assert(pos_is_okay());
	323	}
47d2bc78	324
dbd5418b AT	325	void right(void) {
	326	assert(pos_is_okay());
	327	pos += where->offset + where->add_cnt;
25d99f3b	328	++where;
dbd5418b AT	329	assert(pos_is_okay());
	330	}
	331	};
	332
	333	class Patch {
	334	FileChanges filechanges;
	335	MemBlock add_text;
	336
2fd754cf AT	337	static bool retry_fwrite(char b, size_t l, FILE f, Hashes *hash)
	338	{
	339	size_t r = 1;
	340	while (r > 0 && l > 0)
	341	{
	342	r = fwrite(b, 1, l, f);
	343	if (hash)
	344	hash->Add((unsigned char*)b, r);
	345	l -= r;
	346	b += r;
	347	}
	348	return l == 0;
	349	}
	350
dbd5418b AT	351	static void dump_rest(FILE o, FILE i, Hashes *hash)
	352	{
	353	char buffer[BLOCK_SIZE];
	354	size_t l;
	355	while (0 < (l = fread(buffer, 1, sizeof(buffer), i))) {
2fd754cf AT	356	if (!retry_fwrite(buffer, l, o, hash))
2fd754cf AT	357	break;
dbd5418b AT	358	}
	359	}
	360
	361	static void dump_lines(FILE o, FILE i, size_t n, Hashes *hash)
	362	{
	363	char buffer[BLOCK_SIZE];
dbd5418b AT	364	while (n > 0) {
	365	if (fgets(buffer, sizeof(buffer), i) == 0)
	366	buffer[0] = '\0';
25d99f3b	367	size_t const l = strlen(buffer);
dbd5418b AT	368	if (l == 0 \|\| buffer[l-1] == '\n')
dbd5418b AT	369	n--;
2fd754cf	370	retry_fwrite(buffer, l, o, hash);
dbd5418b AT	371	}
	372	}
	373
	374	static void skip_lines(FILE *i, int n)
	375	{
	376	char buffer[BLOCK_SIZE];
dbd5418b AT	377	while (n > 0) {
	378	if (fgets(buffer, sizeof(buffer), i) == 0)
	379	buffer[0] = '\0';
25d99f3b	380	size_t const l = strlen(buffer);
dbd5418b AT	381	if (l == 0 \|\| buffer[l-1] == '\n')
	382	n--;
	383	}
	384	}
	385
2fd754cf AT	386	static void dump_mem(FILE o, char p, size_t s, Hashes *hash) {
2fd754cf AT	387	retry_fwrite(p, s, o, hash);
dbd5418b AT	388	}
	389
	390	public:
	391
50bd6fd3	392	void read_diff(FileFd &f)
dbd5418b AT	393	{
	394	char buffer[BLOCK_SIZE];
	395	bool cmdwanted = true;
	396
	397	Change ch(0);
50bd6fd3	398	while(f.ReadLine(buffer, sizeof(buffer)))
dbd5418b AT	399	{
	400	if (cmdwanted) {
	401	char m, c;
	402	size_t s, e;
	403	s = strtol(buffer, &m, 10);
	404	if (m == buffer) {
	405	s = e = ch.offset + ch.add_cnt;
	406	c = buffer;
	407	} else if (*m == ',') {
	408	m++;
	409	e = strtol(m, &c, 10);
	410	} else {
	411	e = s;
	412	c = m;
	413	}
	414	switch(*c) {
	415	case 'a':
	416	cmdwanted = false;
	417	ch.add = NULL;
	418	ch.add_cnt = 0;
	419	ch.add_len = 0;
	420	ch.offset = s;
	421	ch.del_cnt = 0;
	422	break;
	423	case 'c':
	424	cmdwanted = false;
	425	ch.add = NULL;
	426	ch.add_cnt = 0;
	427	ch.add_len = 0;
	428	ch.offset = s - 1;
	429	ch.del_cnt = e - s + 1;
	430	break;
	431	case 'd':
	432	ch.offset = s - 1;
	433	ch.del_cnt = e - s + 1;
	434	ch.add = NULL;
	435	ch.add_cnt = 0;
	436	ch.add_len = 0;
	437	filechanges.add_change(ch);
	438	break;
	439	}
2fd754cf	440	} else { /* !cmdwanted */
dbd5418b AT	441	if (buffer[0] == '.' && buffer[1] == '\n') {
	442	cmdwanted = true;
	443	filechanges.add_change(ch);
	444	} else {
	445	char *last = NULL;
	446	char *add;
	447	size_t l;
	448	if (ch.add)
	449	last = ch.add + ch.add_len;
	450	l = strlen(buffer);
	451	add = add_text.add_easy(buffer, l, last);
	452	if (!add) {
	453	ch.add_len += l;
	454	ch.add_cnt++;
	455	} else {
	456	if (ch.add) {
	457	filechanges.add_change(ch);
	458	ch.del_cnt = 0;
	459	}
	460	ch.offset += ch.add_cnt;
	461	ch.add = add;
	462	ch.add_len = l;
	463	ch.add_cnt = 1;
	464	}
	465	}
	466	}
	467	}
	468	}
	469
	470	void write_diff(FILE *f)
	471	{
	472	size_t line = 0;
	473	std::list<struct Change>::reverse_iterator ch;
25d99f3b	474	for (ch = filechanges.rbegin(); ch != filechanges.rend(); ++ch) {
dbd5418b AT	475	line += ch->offset + ch->del_cnt;
	476	}
	477
25d99f3b	478	for (ch = filechanges.rbegin(); ch != filechanges.rend(); ++ch) {
dbd5418b AT	479	std::list<struct Change>::reverse_iterator mg_i, mg_e = ch;
dbd5418b AT	480	while (ch->del_cnt == 0 && ch->offset == 0)
25d99f3b	481	++ch;
dbd5418b AT	482	line -= ch->del_cnt;
	483	if (ch->add_cnt > 0) {
	484	if (ch->del_cnt == 0) {
	485	fprintf(f, "%lua\n", line);
	486	} else if (ch->del_cnt == 1) {
	487	fprintf(f, "%luc\n", line+1);
	488	} else {
	489	fprintf(f, "%lu,%luc\n", line+1, line+ch->del_cnt);
	490	}
	491
	492	mg_i = ch;
	493	do {
	494	dump_mem(f, mg_i->add, mg_i->add_len, NULL);
	495	} while (mg_i-- != mg_e);
	496
	497	fprintf(f, ".\n");
	498	} else if (ch->del_cnt == 1) {
	499	fprintf(f, "%lud\n", line+1);
	500	} else if (ch->del_cnt > 1) {
	501	fprintf(f, "%lu,%lud\n", line+1, line+ch->del_cnt);
	502	}
	503	line -= ch->offset;
	504	}
	505	}
47d2bc78	506
dbd5418b AT	507	void apply_against_file(FILE out, FILE in, Hashes *hash = NULL)
	508	{
	509	std::list<struct Change>::iterator ch;
25d99f3b	510	for (ch = filechanges.begin(); ch != filechanges.end(); ++ch) {
dbd5418b AT	511	dump_lines(out, in, ch->offset, hash);
	512	skip_lines(in, ch->del_cnt);
	513	dump_mem(out, ch->add, ch->add_len, hash);
	514	}
	515	dump_rest(out, in, hash);
47d2bc78	516	}
dbd5418b AT	517	};
dbd5418b AT	518
dbd5418b AT	519	class RredMethod : public pkgAcqMethod {
	520	private:
	521	bool Debug;
dbd5418b AT	522
dbd5418b AT	523	protected:
dbd5418b AT	524	virtual bool Fetch(FetchItem *Itm) {
	525	Debug = _config->FindB("Debug::pkgAcquire::RRed", false);
	526	URI Get = Itm->Uri;
	527	std::string Path = Get.Host + Get.Path; // rred:/path - no host
	528
	529	FetchResult Res;
	530	Res.Filename = Itm->DestFile;
50bd6fd3 DK	531	if (Itm->Uri.empty())
50bd6fd3 DK	532	{
dbd5418b AT	533	Path = Itm->DestFile;
	534	Itm->DestFile.append(".result");
	535	} else
	536	URIStart(Res);
	537
50bd6fd3	538	std::vector<std::string> patchpaths;
dbd5418b AT	539	Patch patch;
dbd5418b AT	540
50bd6fd3	541	if (FileExists(Path + ".ed") == true)
dbd5418b	542	patchpaths.push_back(Path + ".ed");
50bd6fd3 DK	543	else
	544	{
	545	_error->PushToStack();
	546	std::vector<std::string> patches = GetListOfFilesInDir(flNotFile(Path), "gz", true, false);
	547	_error->RevertToStack();
	548
	549	std::string const baseName = Path + ".ed.";
	550	for (std::vector<std::string>::const_iterator p = patches.begin();
	551	p != patches.end(); ++p)
	552	if (p->compare(0, baseName.length(), baseName) == 0)
	553	patchpaths.push_back(*p);
dbd5418b AT	554	}
	555
	556	std::string patch_name;
	557	for (std::vector<std::string>::iterator I = patchpaths.begin();
	558	I != patchpaths.end();
25d99f3b	559	++I)
dbd5418b AT	560	{
	561	patch_name = *I;
	562	if (Debug == true)
	563	std::clog << "Patching " << Path << " with " << patch_name
	564	<< std::endl;
	565
50bd6fd3 DK	566	FileFd p;
	567	// all patches are compressed, even if the name doesn't reflect it
	568	if (p.Open(patch_name, FileFd::ReadOnly, FileFd::Gzip) == false) {
	569	std::cerr << "Could not open patch file " << patch_name << std::endl;
	570	_error->DumpErrors(std::cerr);
dbd5418b AT	571	abort();
	572	}
	573	patch.read_diff(p);
50bd6fd3	574	p.Close();
dbd5418b AT	575	}
	576
	577	if (Debug == true)
	578	std::clog << "Applying patches against " << Path
	579	<< " and writing results to " << Itm->DestFile
	580	<< std::endl;
	581
	582	FILE *inp = fopen(Path.c_str(), "r");
	583	FILE *out = fopen(Itm->DestFile.c_str(), "w");
	584
	585	Hashes hash;
	586
	587	patch.apply_against_file(out, inp, &hash);
	588
	589	fclose(out);
	590	fclose(inp);
	591
	592	if (Debug == true) {
	593	std::clog << "rred: finished file patching of " << Path << "." << std::endl;
	594	}
	595
	596	struct stat bufbase, bufpatch;
	597	if (stat(Path.c_str(), &bufbase) != 0 \|\|
	598	stat(patch_name.c_str(), &bufpatch) != 0)
	599	return _error->Errno("stat", _("Failed to stat"));
	600
246bbb61	601	struct timeval times[2];
25d99f3b DK	602	times[0].tv_sec = bufbase.st_atime;
25d99f3b DK	603	times[1].tv_sec = bufpatch.st_mtime;
246bbb61 DK	604	times[0].tv_usec = times[1].tv_usec = 0;
	605	if (utimes(Itm->DestFile.c_str(), times) != 0)
	606	return _error->Errno("utimes",_("Failed to set modification time"));
dbd5418b AT	607
	608	if (stat(Itm->DestFile.c_str(), &bufbase) != 0)
	609	return _error->Errno("stat", _("Failed to stat"));
	610
	611	Res.LastModified = bufbase.st_mtime;
	612	Res.Size = bufbase.st_size;
	613	Res.TakeHashes(hash);
	614	URIDone(Res);
	615
	616	return true;
	617	}
	618
	619	public:
25d99f3b	620	RredMethod() : pkgAcqMethod("2.0",SingleInstance \| SendConfig), Debug(false) {}
bb1293d9	621	};
dbd5418b AT	622
	623	int main(int argc, char **argv)
	624	{
	625	int i;
	626	bool just_diff = true;
	627	Patch patch;
	628
	629	if (argc <= 1) {
	630	RredMethod Mth;
	631	return Mth.Run();
	632	}
	633
	634	if (argc > 1 && strcmp(argv[1], "-f") == 0) {
	635	just_diff = false;
	636	i = 2;
	637	} else {
	638	i = 1;
	639	}
	640
	641	for (; i < argc; i++) {
50bd6fd3 DK	642	FileFd p;
	643	if (p.Open(argv[i], FileFd::ReadOnly) == false) {
	644	_error->DumpErrors(std::cerr);
dbd5418b AT	645	exit(1);
	646	}
	647	patch.read_diff(p);
	648	}
	649
	650	if (just_diff) {
	651	patch.write_diff(stdout);
	652	} else {
	653	FILE out, inp;
	654	out = stdout;
	655	inp = stdin;
	656
	657	patch.apply_against_file(out, inp);
	658	}
	659	return 0;
2e178d1c	660	}