+ 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();
+ }
projects / apt.git / blobdiff