1 /*===- InstrProfilingFile.c - Write instrumentation to a file -------------===*\
2 |*
3 |* The LLVM Compiler Infrastructure
4 |*
5 |* This file is distributed under the University of Illinois Open Source
6 |* License. See LICENSE.TXT for details.
7 |*
8 \*===----------------------------------------------------------------------===*/
9
10 #include "InstrProfiling.h"
11 #include "InstrProfilingInternal.h"
12 #include "InstrProfilingUtil.h"
13 #include <errno.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17
18 #define UNCONST(ptr) ((void *)(uintptr_t)(ptr))
19
20 /* Return 1 if there is an error, otherwise return 0. */
fileWriter(ProfDataIOVec * IOVecs,uint32_t NumIOVecs,void ** WriterCtx)21 static uint32_t fileWriter(ProfDataIOVec *IOVecs, uint32_t NumIOVecs,
22 void **WriterCtx) {
23 uint32_t I;
24 FILE *File = (FILE *)*WriterCtx;
25 for (I = 0; I < NumIOVecs; I++) {
26 if (fwrite(IOVecs[I].Data, IOVecs[I].ElmSize, IOVecs[I].NumElm, File) !=
27 IOVecs[I].NumElm)
28 return 1;
29 }
30 return 0;
31 }
32
writeFile(FILE * File)33 static int writeFile(FILE *File) {
34 uint8_t *ValueDataBegin = NULL;
35 const uint64_t ValueDataSize =
36 __llvm_profile_gather_value_data(&ValueDataBegin);
37 int r = llvmWriteProfData(fileWriter, File, ValueDataBegin, ValueDataSize);
38 free(ValueDataBegin);
39 return r;
40 }
41
writeFileWithName(const char * OutputName)42 static int writeFileWithName(const char *OutputName) {
43 int RetVal;
44 FILE *OutputFile;
45 if (!OutputName || !OutputName[0])
46 return -1;
47
48 /* Append to the file to support profiling multiple shared objects. */
49 OutputFile = fopen(OutputName, "ab");
50 if (!OutputFile)
51 return -1;
52
53 RetVal = writeFile(OutputFile);
54
55 fclose(OutputFile);
56 return RetVal;
57 }
58
59 COMPILER_RT_WEAK int __llvm_profile_OwnsFilename = 0;
60 COMPILER_RT_WEAK const char *__llvm_profile_CurrentFilename = NULL;
61
truncateCurrentFile(void)62 static void truncateCurrentFile(void) {
63 const char *Filename;
64 FILE *File;
65
66 Filename = __llvm_profile_CurrentFilename;
67 if (!Filename || !Filename[0])
68 return;
69
70 /* Create the directory holding the file, if needed. */
71 if (strchr(Filename, '/')) {
72 char *Copy = malloc(strlen(Filename) + 1);
73 strcpy(Copy, Filename);
74 __llvm_profile_recursive_mkdir(Copy);
75 free(Copy);
76 }
77
78 /* Truncate the file. Later we'll reopen and append. */
79 File = fopen(Filename, "w");
80 if (!File)
81 return;
82 fclose(File);
83 }
84
setFilename(const char * Filename,int OwnsFilename)85 static void setFilename(const char *Filename, int OwnsFilename) {
86 /* Check if this is a new filename and therefore needs truncation. */
87 int NewFile = !__llvm_profile_CurrentFilename ||
88 (Filename && strcmp(Filename, __llvm_profile_CurrentFilename));
89 if (__llvm_profile_OwnsFilename)
90 free(UNCONST(__llvm_profile_CurrentFilename));
91
92 __llvm_profile_CurrentFilename = Filename;
93 __llvm_profile_OwnsFilename = OwnsFilename;
94
95 /* If not a new file, append to support profiling multiple shared objects. */
96 if (NewFile)
97 truncateCurrentFile();
98 }
99
resetFilenameToDefault(void)100 static void resetFilenameToDefault(void) { setFilename("default.profraw", 0); }
101
102 int getpid(void);
setFilenamePossiblyWithPid(const char * Filename)103 static int setFilenamePossiblyWithPid(const char *Filename) {
104 #define MAX_PID_SIZE 16
105 char PidChars[MAX_PID_SIZE] = {0};
106 int NumPids = 0, PidLength = 0;
107 char *Allocated;
108 int I, J;
109
110 /* Reset filename on NULL, except with env var which is checked by caller. */
111 if (!Filename) {
112 resetFilenameToDefault();
113 return 0;
114 }
115
116 /* Check the filename for "%p", which indicates a pid-substitution. */
117 for (I = 0; Filename[I]; ++I)
118 if (Filename[I] == '%' && Filename[++I] == 'p')
119 if (!NumPids++) {
120 PidLength = snprintf(PidChars, MAX_PID_SIZE, "%d", getpid());
121 if (PidLength <= 0)
122 return -1;
123 }
124 if (!NumPids) {
125 setFilename(Filename, 0);
126 return 0;
127 }
128
129 /* Allocate enough space for the substituted filename. */
130 Allocated = malloc(I + NumPids*(PidLength - 2) + 1);
131 if (!Allocated)
132 return -1;
133
134 /* Construct the new filename. */
135 for (I = 0, J = 0; Filename[I]; ++I)
136 if (Filename[I] == '%') {
137 if (Filename[++I] == 'p') {
138 memcpy(Allocated + J, PidChars, PidLength);
139 J += PidLength;
140 }
141 /* Drop any unknown substitutions. */
142 } else
143 Allocated[J++] = Filename[I];
144 Allocated[J] = 0;
145
146 /* Use the computed name. */
147 setFilename(Allocated, 1);
148 return 0;
149 }
150
setFilenameFromEnvironment(void)151 static int setFilenameFromEnvironment(void) {
152 const char *Filename = getenv("LLVM_PROFILE_FILE");
153
154 if (!Filename || !Filename[0])
155 return -1;
156
157 return setFilenamePossiblyWithPid(Filename);
158 }
159
setFilenameAutomatically(void)160 static void setFilenameAutomatically(void) {
161 if (!setFilenameFromEnvironment())
162 return;
163
164 resetFilenameToDefault();
165 }
166
167 COMPILER_RT_VISIBILITY
__llvm_profile_initialize_file(void)168 void __llvm_profile_initialize_file(void) {
169 /* Check if the filename has been initialized. */
170 if (__llvm_profile_CurrentFilename)
171 return;
172
173 /* Detect the filename and truncate. */
174 setFilenameAutomatically();
175 }
176
177 COMPILER_RT_VISIBILITY
__llvm_profile_set_filename(const char * Filename)178 void __llvm_profile_set_filename(const char *Filename) {
179 setFilenamePossiblyWithPid(Filename);
180 }
181
182 COMPILER_RT_VISIBILITY
__llvm_profile_override_default_filename(const char * Filename)183 void __llvm_profile_override_default_filename(const char *Filename) {
184 /* If the env var is set, skip setting filename from argument. */
185 const char *Env_Filename = getenv("LLVM_PROFILE_FILE");
186 if (Env_Filename && Env_Filename[0])
187 return;
188 setFilenamePossiblyWithPid(Filename);
189 }
190
191 COMPILER_RT_VISIBILITY
__llvm_profile_write_file(void)192 int __llvm_profile_write_file(void) {
193 int rc;
194
195 GetEnvHook = &getenv;
196 /* Check the filename. */
197 if (!__llvm_profile_CurrentFilename) {
198 PROF_ERR("LLVM Profile: Failed to write file : %s\n", "Filename not set");
199 return -1;
200 }
201
202 /* Write the file. */
203 rc = writeFileWithName(__llvm_profile_CurrentFilename);
204 if (rc)
205 PROF_ERR("LLVM Profile: Failed to write file \"%s\": %s\n",
206 __llvm_profile_CurrentFilename, strerror(errno));
207 return rc;
208 }
209
writeFileWithoutReturn(void)210 static void writeFileWithoutReturn(void) { __llvm_profile_write_file(); }
211
212 COMPILER_RT_VISIBILITY
__llvm_profile_register_write_file_atexit(void)213 int __llvm_profile_register_write_file_atexit(void) {
214 static int HasBeenRegistered = 0;
215
216 if (HasBeenRegistered)
217 return 0;
218
219 HasBeenRegistered = 1;
220 return atexit(writeFileWithoutReturn);
221 }
222