| /* Generated by re2c */ |
| // Copyright 2011 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "depfile_parser.h" |
| #include "util.h" |
| |
| #include <algorithm> |
| |
| using namespace std; |
| |
| DepfileParser::DepfileParser(DepfileParserOptions options) |
| : options_(options) |
| { |
| } |
| |
| // A note on backslashes in Makefiles, from reading the docs: |
| // Backslash-newline is the line continuation character. |
| // Backslash-# escapes a # (otherwise meaningful as a comment start). |
| // Backslash-% escapes a % (otherwise meaningful as a special). |
| // Finally, quoting the GNU manual, "Backslashes that are not in danger |
| // of quoting ‘%’ characters go unmolested." |
| // How do you end a line with a backslash? The netbsd Make docs suggest |
| // reading the result of a shell command echoing a backslash! |
| // |
| // Rather than implement all of above, we follow what GCC/Clang produces: |
| // Backslashes escape a space or hash sign. |
| // When a space is preceded by 2N+1 backslashes, it is represents N backslashes |
| // followed by space. |
| // When a space is preceded by 2N backslashes, it represents 2N backslashes at |
| // the end of a filename. |
| // A hash sign is escaped by a single backslash. All other backslashes remain |
| // unchanged. |
| // |
| // If anyone actually has depfiles that rely on the more complicated |
| // behavior we can adjust this. |
| bool DepfileParser::Parse(string* content, string* err) { |
| // in: current parser input point. |
| // end: end of input. |
| // parsing_targets: whether we are parsing targets or dependencies. |
| char* in = &(*content)[0]; |
| char* end = in + content->size(); |
| bool have_target = false; |
| bool parsing_targets = true; |
| bool poisoned_input = false; |
| bool is_empty = true; |
| while (in < end) { |
| bool have_newline = false; |
| // out: current output point (typically same as in, but can fall behind |
| // as we de-escape backslashes). |
| char* out = in; |
| // filename: start of the current parsed filename. |
| char* filename = out; |
| for (;;) { |
| // start: beginning of the current parsed span. |
| const char* start = in; |
| char* yymarker = NULL; |
| |
| { |
| unsigned char yych; |
| static const unsigned char yybm[] = { |
| 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 128, 0, 0, 0, 128, 0, 0, |
| 128, 128, 0, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 0, 0, 128, 0, 0, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 0, 128, 0, 128, |
| 0, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 0, 128, 128, 0, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| 128, 128, 128, 128, 128, 128, 128, 128, |
| }; |
| yych = *in; |
| if (yybm[0+yych] & 128) { |
| goto yy9; |
| } |
| if (yych <= '\r') { |
| if (yych <= '\t') { |
| if (yych >= 0x01) goto yy4; |
| } else { |
| if (yych <= '\n') goto yy6; |
| if (yych <= '\f') goto yy4; |
| goto yy8; |
| } |
| } else { |
| if (yych <= '$') { |
| if (yych <= '#') goto yy4; |
| goto yy12; |
| } else { |
| if (yych <= '?') goto yy4; |
| if (yych <= '\\') goto yy13; |
| goto yy4; |
| } |
| } |
| ++in; |
| { |
| break; |
| } |
| yy4: |
| ++in; |
| yy5: |
| { |
| // For any other character (e.g. whitespace), swallow it here, |
| // allowing the outer logic to loop around again. |
| break; |
| } |
| yy6: |
| ++in; |
| { |
| // A newline ends the current file name and the current rule. |
| have_newline = true; |
| break; |
| } |
| yy8: |
| yych = *++in; |
| if (yych == '\n') goto yy6; |
| goto yy5; |
| yy9: |
| yych = *++in; |
| if (yybm[0+yych] & 128) { |
| goto yy9; |
| } |
| yy11: |
| { |
| // Got a span of plain text. |
| int len = (int)(in - start); |
| // Need to shift it over if we're overwriting backslashes. |
| if (out < start) |
| memmove(out, start, len); |
| out += len; |
| continue; |
| } |
| yy12: |
| yych = *++in; |
| if (yych == '$') goto yy14; |
| goto yy5; |
| yy13: |
| yych = *(yymarker = ++in); |
| if (yych <= ' ') { |
| if (yych <= '\n') { |
| if (yych <= 0x00) goto yy5; |
| if (yych <= '\t') goto yy16; |
| goto yy17; |
| } else { |
| if (yych == '\r') goto yy19; |
| if (yych <= 0x1F) goto yy16; |
| goto yy21; |
| } |
| } else { |
| if (yych <= '9') { |
| if (yych == '#') goto yy23; |
| goto yy16; |
| } else { |
| if (yych <= ':') goto yy25; |
| if (yych == '\\') goto yy27; |
| goto yy16; |
| } |
| } |
| yy14: |
| ++in; |
| { |
| // De-escape dollar character. |
| *out++ = '$'; |
| continue; |
| } |
| yy16: |
| ++in; |
| goto yy11; |
| yy17: |
| ++in; |
| { |
| // A line continuation ends the current file name. |
| break; |
| } |
| yy19: |
| yych = *++in; |
| if (yych == '\n') goto yy17; |
| in = yymarker; |
| goto yy5; |
| yy21: |
| ++in; |
| { |
| // 2N+1 backslashes plus space -> N backslashes plus space. |
| int len = (int)(in - start); |
| int n = len / 2 - 1; |
| if (out < start) |
| memset(out, '\\', n); |
| out += n; |
| *out++ = ' '; |
| continue; |
| } |
| yy23: |
| ++in; |
| { |
| // De-escape hash sign, but preserve other leading backslashes. |
| int len = (int)(in - start); |
| if (len > 2 && out < start) |
| memset(out, '\\', len - 2); |
| out += len - 2; |
| *out++ = '#'; |
| continue; |
| } |
| yy25: |
| yych = *++in; |
| if (yych <= '\f') { |
| if (yych <= 0x00) goto yy28; |
| if (yych <= 0x08) goto yy26; |
| if (yych <= '\n') goto yy28; |
| } else { |
| if (yych <= '\r') goto yy28; |
| if (yych == ' ') goto yy28; |
| } |
| yy26: |
| { |
| // De-escape colon sign, but preserve other leading backslashes. |
| // Regular expression uses lookahead to make sure that no whitespace |
| // nor EOF follows. In that case it'd be the : at the end of a target |
| int len = (int)(in - start); |
| if (len > 2 && out < start) |
| memset(out, '\\', len - 2); |
| out += len - 2; |
| *out++ = ':'; |
| continue; |
| } |
| yy27: |
| yych = *++in; |
| if (yych <= ' ') { |
| if (yych <= '\n') { |
| if (yych <= 0x00) goto yy11; |
| if (yych <= '\t') goto yy16; |
| goto yy11; |
| } else { |
| if (yych == '\r') goto yy11; |
| if (yych <= 0x1F) goto yy16; |
| goto yy30; |
| } |
| } else { |
| if (yych <= '9') { |
| if (yych == '#') goto yy23; |
| goto yy16; |
| } else { |
| if (yych <= ':') goto yy25; |
| if (yych == '\\') goto yy32; |
| goto yy16; |
| } |
| } |
| yy28: |
| ++in; |
| { |
| // Backslash followed by : and whitespace. |
| // It is therefore normal text and not an escaped colon |
| int len = (int)(in - start - 1); |
| // Need to shift it over if we're overwriting backslashes. |
| if (out < start) |
| memmove(out, start, len); |
| out += len; |
| if (*(in - 1) == '\n') |
| have_newline = true; |
| break; |
| } |
| yy30: |
| ++in; |
| { |
| // 2N backslashes plus space -> 2N backslashes, end of filename. |
| int len = (int)(in - start); |
| if (out < start) |
| memset(out, '\\', len - 1); |
| out += len - 1; |
| break; |
| } |
| yy32: |
| yych = *++in; |
| if (yych <= ' ') { |
| if (yych <= '\n') { |
| if (yych <= 0x00) goto yy11; |
| if (yych <= '\t') goto yy16; |
| goto yy11; |
| } else { |
| if (yych == '\r') goto yy11; |
| if (yych <= 0x1F) goto yy16; |
| goto yy21; |
| } |
| } else { |
| if (yych <= '9') { |
| if (yych == '#') goto yy23; |
| goto yy16; |
| } else { |
| if (yych <= ':') goto yy25; |
| if (yych == '\\') goto yy27; |
| goto yy16; |
| } |
| } |
| } |
| |
| } |
| |
| int len = (int)(out - filename); |
| const bool is_dependency = !parsing_targets; |
| if (len > 0 && filename[len - 1] == ':') { |
| len--; // Strip off trailing colon, if any. |
| parsing_targets = false; |
| have_target = true; |
| } |
| |
| if (len > 0) { |
| is_empty = false; |
| StringPiece piece = StringPiece(filename, len); |
| // If we've seen this as an input before, skip it. |
| std::vector<StringPiece>::iterator pos = std::find(ins_.begin(), ins_.end(), piece); |
| if (pos == ins_.end()) { |
| if (is_dependency) { |
| if (poisoned_input) { |
| *err = "inputs may not also have inputs"; |
| return false; |
| } |
| // New input. |
| ins_.push_back(piece); |
| } else { |
| // Check for a new output. |
| if (std::find(outs_.begin(), outs_.end(), piece) == outs_.end()) |
| outs_.push_back(piece); |
| } |
| } else if (!is_dependency) { |
| // We've passed an input on the left side; reject new inputs. |
| poisoned_input = true; |
| } |
| } |
| |
| if (have_newline) { |
| // A newline ends a rule so the next filename will be a new target. |
| parsing_targets = true; |
| poisoned_input = false; |
| } |
| } |
| if (!have_target && !is_empty) { |
| *err = "expected ':' in depfile"; |
| return false; |
| } |
| return true; |
| } |
