OpenTTD Source  20241121-master-g67a0fccfad
script_info_dummy.cpp
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1 /*
2  * This file is part of OpenTTD.
3  * OpenTTD 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, version 2.
4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6  */
7 
10 #include "../stdafx.h"
11 #include <squirrel.h>
12 
13 #include "../string_func.h"
14 #include "../strings_func.h"
15 #include "../3rdparty/fmt/format.h"
16 
17 #include "../safeguards.h"
18 
19 /* The reason this exists in C++, is that a user can trash their ai/ or game/ dir,
20  * leaving no Scripts available. The complexity to solve this is insane, and
21  * therefore the alternative is used, and make sure there is always a Script
22  * available, no matter what the situation is. By defining it in C++, there
23  * is simply no way a user can delete it, and therefore safe to use. It has
24  * to be noted that this Script is complete invisible for the user, and impossible
25  * to select manual. It is a fail-over in case no Scripts are available.
26  */
27 
29 void Script_CreateDummyInfo(HSQUIRRELVM vm, const char *type, const char *dir)
30 {
31  std::string dummy_script = fmt::format(
32  "class Dummy{0} extends {0}Info {{\n"
33  "function GetAuthor() {{ return \"OpenTTD Developers Team\"; }}\n"
34  "function GetName() {{ return \"Dummy{0}\"; }}\n"
35  "function GetShortName() {{ return \"DUMM\"; }}\n"
36  "function GetDescription() {{ return \"A Dummy {0} that is loaded when your {1}/ dir is empty\"; }}\n"
37  "function GetVersion() {{ return 1; }}\n"
38  "function GetDate() {{ return \"2008-07-26\"; }}\n"
39  "function CreateInstance() {{ return \"Dummy{0}\"; }}\n"
40  "}} RegisterDummy{0}(Dummy{0}());\n", type, dir);
41 
42  sq_pushroottable(vm);
43 
44  /* Load and run the script */
45  if (SQ_SUCCEEDED(sq_compilebuffer(vm, dummy_script.c_str(), dummy_script.size(), "dummy", SQTrue))) {
46  sq_push(vm, -2);
47  if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue))) {
48  sq_pop(vm, 1);
49  return;
50  }
51  }
52  NOT_REACHED();
53 }
54 
61 static std::vector<std::string> EscapeQuotesAndSlashesAndSplitOnNewLines(const std::string &message)
62 {
63  std::vector<std::string> messages;
64 
65  std::string safe_message;
66  for (auto c : message) {
67  if (c == '\n') {
68  messages.emplace_back(std::move(safe_message));
69  continue;
70  }
71 
72  if (c == '"' || c == '\\') safe_message.push_back('\\');
73  safe_message.push_back(c);
74  }
75  messages.emplace_back(std::move(safe_message));
76  return messages;
77 }
78 
80 void Script_CreateDummy(HSQUIRRELVM vm, StringID string, const char *type)
81 {
82  /* We want to translate the error message.
83  * We do this in three steps:
84  * 1) We get the error message, escape quotes and slashes, and split on
85  * newlines because Log.Error terminates passed strings at newlines.
86  */
87  std::string error_message = GetString(string);
88  std::vector<std::string> messages = EscapeQuotesAndSlashesAndSplitOnNewLines(error_message);
89 
90  /* 2) We construct the AI's code. This is done by merging a header, body and footer */
91  std::string dummy_script;
92  auto back_inserter = std::back_inserter(dummy_script);
93  /* Just a rough ballpark estimate. */
94  dummy_script.reserve(error_message.size() + 128 + 64 * messages.size());
95 
96  fmt::format_to(back_inserter, "class Dummy{0} extends {0}Controller {{\n function Start()\n {{\n", type);
97  for (std::string &message : messages) {
98  fmt::format_to(back_inserter, " {}Log.Error(\"{}\");\n", type, message);
99  }
100  dummy_script += " }\n}\n";
101 
102  /* 3) Finally we load and run the script */
103  sq_pushroottable(vm);
104  if (SQ_SUCCEEDED(sq_compilebuffer(vm, dummy_script.c_str(), dummy_script.size(), "dummy", SQTrue))) {
105  sq_push(vm, -2);
106  if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue))) {
107  sq_pop(vm, 1);
108  return;
109  }
110  }
111  NOT_REACHED();
112 }
static std::vector< std::string > EscapeQuotesAndSlashesAndSplitOnNewLines(const std::string &message)
Split the given message on newlines (' ') and escape quotes and (back)slashes, so they can be properl...
void Script_CreateDummyInfo(HSQUIRRELVM vm, const char *type, const char *dir)
Run the dummy info.nut.
void Script_CreateDummy(HSQUIRRELVM vm, StringID string, const char *type)
Run the dummy AI and let it generate an error message.
std::string GetString(StringID string)
Resolve the given StringID into a std::string with all the associated DParam lookups and formatting.
Definition: strings.cpp:319
uint32_t StringID
Numeric value that represents a string, independent of the selected language.
Definition: strings_type.h:16