1//===-- options_parser.cpp --------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "gwp_asan/optional/options_parser.h"
10#include "gwp_asan/optional/printf.h"
11#include "gwp_asan/utilities.h"
12
13#include <assert.h>
14#include <stdarg.h>
15#include <stdint.h>
16#include <stdlib.h>
17#include <string.h>
18
19namespace {
20enum class OptionType : uint8_t {
21 OT_bool,
22 OT_int,
23};
24
25#define InvokeIfNonNull(Printf, ...) \
26 do { \
27 if (Printf) \
28 Printf(__VA_ARGS__); \
29 } while (0);
30
31class OptionParser {
32public:
33 explicit OptionParser(gwp_asan::Printf_t PrintfForWarnings)
34 : Printf(PrintfForWarnings) {}
35 void registerOption(const char *Name, const char *Desc, OptionType Type,
36 void *Var);
37 void parseString(const char *S);
38 void printOptionDescriptions();
39
40private:
41 // Calculate at compile-time how many options are available.
42#define GWP_ASAN_OPTION(...) +1
43 static constexpr size_t MaxOptions = 0
44#include "gwp_asan/options.inc"
45 ;
46#undef GWP_ASAN_OPTION
47
48 struct Option {
49 const char *Name;
50 const char *Desc;
51 OptionType Type;
52 void *Var;
53 } Options[MaxOptions];
54
55 size_t NumberOfOptions = 0;
56 const char *Buffer = nullptr;
57 uintptr_t Pos = 0;
58 gwp_asan::Printf_t Printf = nullptr;
59
60 void skipWhitespace();
61 void parseOptions();
62 bool parseOption();
63 bool setOptionToValue(const char *Name, const char *Value);
64};
65
66void OptionParser::printOptionDescriptions() {
67 InvokeIfNonNull(Printf, "GWP-ASan: Available options:\n");
68 for (size_t I = 0; I < NumberOfOptions; ++I)
69 InvokeIfNonNull(Printf, "\t%s\n\t\t- %s\n", Options[I].Name,
70 Options[I].Desc);
71}
72
73bool isSeparator(char C) {
74 return C == ' ' || C == ',' || C == ':' || C == '\n' || C == '\t' ||
75 C == '\r';
76}
77
78bool isSeparatorOrNull(char C) { return !C || isSeparator(C); }
79
80void OptionParser::skipWhitespace() {
81 while (isSeparator(C: Buffer[Pos]))
82 ++Pos;
83}
84
85bool OptionParser::parseOption() {
86 const uintptr_t NameStart = Pos;
87 while (Buffer[Pos] != '=' && !isSeparatorOrNull(C: Buffer[Pos]))
88 ++Pos;
89
90 const char *Name = Buffer + NameStart;
91 if (Buffer[Pos] != '=') {
92 InvokeIfNonNull(Printf, "GWP-ASan: Expected '=' when parsing option '%s'.",
93 Name);
94 return false;
95 }
96 const uintptr_t ValueStart = ++Pos;
97 const char *Value;
98 if (Buffer[Pos] == '\'' || Buffer[Pos] == '"') {
99 const char Quote = Buffer[Pos++];
100 while (Buffer[Pos] != 0 && Buffer[Pos] != Quote)
101 ++Pos;
102 if (Buffer[Pos] == 0) {
103 InvokeIfNonNull(Printf, "GWP-ASan: Unterminated string in option '%s'.",
104 Name);
105 return false;
106 }
107 Value = Buffer + ValueStart + 1;
108 ++Pos; // consume the closing quote
109 } else {
110 while (!isSeparatorOrNull(C: Buffer[Pos]))
111 ++Pos;
112 Value = Buffer + ValueStart;
113 }
114
115 return setOptionToValue(Name, Value);
116}
117
118void OptionParser::parseOptions() {
119 while (true) {
120 skipWhitespace();
121 if (Buffer[Pos] == 0)
122 break;
123 if (!parseOption()) {
124 InvokeIfNonNull(Printf, "GWP-ASan: Options parsing failed.\n");
125 return;
126 }
127 }
128}
129
130void OptionParser::parseString(const char *S) {
131 if (!S)
132 return;
133 Buffer = S;
134 Pos = 0;
135 parseOptions();
136}
137
138bool parseBool(const char *Value, bool *b) {
139 if (strncmp(s1: Value, s2: "0", n: 1) == 0 || strncmp(s1: Value, s2: "no", n: 2) == 0 ||
140 strncmp(s1: Value, s2: "false", n: 5) == 0) {
141 *b = false;
142 return true;
143 }
144 if (strncmp(s1: Value, s2: "1", n: 1) == 0 || strncmp(s1: Value, s2: "yes", n: 3) == 0 ||
145 strncmp(s1: Value, s2: "true", n: 4) == 0) {
146 *b = true;
147 return true;
148 }
149 return false;
150}
151
152bool OptionParser::setOptionToValue(const char *Name, const char *Value) {
153 for (size_t I = 0; I < NumberOfOptions; ++I) {
154 const uintptr_t Len = strlen(s: Options[I].Name);
155 if (strncmp(s1: Name, s2: Options[I].Name, n: Len) != 0 || Name[Len] != '=')
156 continue;
157 bool Ok = false;
158 switch (Options[I].Type) {
159 case OptionType::OT_bool:
160 Ok = parseBool(Value, b: reinterpret_cast<bool *>(Options[I].Var));
161 if (!Ok)
162 InvokeIfNonNull(
163 Printf, "GWP-ASan: Invalid boolean value '%s' for option '%s'.\n",
164 Value, Options[I].Name);
165 break;
166 case OptionType::OT_int:
167 char *ValueEnd;
168 *reinterpret_cast<int *>(Options[I].Var) =
169 static_cast<int>(strtol(nptr: Value, endptr: &ValueEnd, base: 10));
170 Ok =
171 *ValueEnd == '"' || *ValueEnd == '\'' || isSeparatorOrNull(C: *ValueEnd);
172 if (!Ok)
173 InvokeIfNonNull(
174 Printf, "GWP-ASan: Invalid integer value '%s' for option '%s'.\n",
175 Value, Options[I].Name);
176 break;
177 }
178 return Ok;
179 }
180
181 InvokeIfNonNull(Printf, "GWP-ASan: Unknown option '%s'.", Name);
182 return true;
183}
184
185void OptionParser::registerOption(const char *Name, const char *Desc,
186 OptionType Type, void *Var) {
187 assert(NumberOfOptions < MaxOptions &&
188 "GWP-ASan Error: Ran out of space for options.\n");
189 Options[NumberOfOptions].Name = Name;
190 Options[NumberOfOptions].Desc = Desc;
191 Options[NumberOfOptions].Type = Type;
192 Options[NumberOfOptions].Var = Var;
193 ++NumberOfOptions;
194}
195
196void registerGwpAsanOptions(OptionParser *parser,
197 gwp_asan::options::Options *o) {
198#define GWP_ASAN_OPTION(Type, Name, DefaultValue, Description) \
199 parser->registerOption(#Name, Description, OptionType::OT_##Type, &o->Name);
200#include "gwp_asan/options.inc"
201#undef GWP_ASAN_OPTION
202}
203
204const char *getGwpAsanDefaultOptions() {
205 return (__gwp_asan_default_options) ? __gwp_asan_default_options() : "";
206}
207
208gwp_asan::options::Options *getOptionsInternal() {
209 static gwp_asan::options::Options GwpAsanOptions;
210 return &GwpAsanOptions;
211}
212} // anonymous namespace
213
214namespace gwp_asan {
215namespace options {
216
217void initOptions(const char *OptionsStr, Printf_t PrintfForWarnings) {
218 Options *o = getOptionsInternal();
219 o->setDefaults();
220
221 OptionParser Parser(PrintfForWarnings);
222 registerGwpAsanOptions(parser: &Parser, o);
223
224 // Override from the weak function definition in this executable.
225 Parser.parseString(S: getGwpAsanDefaultOptions());
226
227 // Override from the provided options string.
228 Parser.parseString(S: OptionsStr);
229
230 if (o->help)
231 Parser.printOptionDescriptions();
232
233 if (!o->Enabled)
234 return;
235
236 if (o->MaxSimultaneousAllocations <= 0) {
237 InvokeIfNonNull(
238 PrintfForWarnings,
239 "GWP-ASan ERROR: MaxSimultaneousAllocations must be > 0 when GWP-ASan "
240 "is enabled.\n");
241 o->Enabled = false;
242 }
243 if (o->SampleRate <= 0) {
244 InvokeIfNonNull(
245 PrintfForWarnings,
246 "GWP-ASan ERROR: SampleRate must be > 0 when GWP-ASan is enabled.\n");
247 o->Enabled = false;
248 }
249}
250
251void initOptions(Printf_t PrintfForWarnings) {
252 initOptions(OptionsStr: getenv(name: "GWP_ASAN_OPTIONS"), PrintfForWarnings);
253}
254
255Options &getOptions() { return *getOptionsInternal(); }
256
257} // namespace options
258} // namespace gwp_asan
259