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comparison: toolkit/components/telemetry/gen-histogram-data.py
toolkit/components/telemetry/gen-histogram-data.py
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| -1:000000000000 | 0:3ee2a98a54b1 |
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| 1 # This Source Code Form is subject to the terms of the Mozilla Public | |
| 2 # License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 3 # file, You can obtain one at http://mozilla.org/MPL/2.0/. | |
| 4 | |
| 5 # Write out histogram information for C++. The histograms are defined | |
| 6 # in a file provided as a command-line argument. | |
| 7 | |
| 8 from __future__ import with_statement | |
| 9 | |
| 10 import sys | |
| 11 import histogram_tools | |
| 12 import itertools | |
| 13 | |
| 14 banner = """/* This file is auto-generated, see gen-histogram-data.py. */ | |
| 15 """ | |
| 16 | |
| 17 # Write out the gHistograms array. | |
| 18 | |
| 19 class StringTable: | |
| 20 def __init__(self): | |
| 21 self.current_index = 0; | |
| 22 self.table = {} | |
| 23 | |
| 24 def c_strlen(self, string): | |
| 25 return len(string) + 1 | |
| 26 | |
| 27 def stringIndex(self, string): | |
| 28 if string in self.table: | |
| 29 return self.table[string] | |
| 30 else: | |
| 31 result = self.current_index | |
| 32 self.table[string] = result | |
| 33 self.current_index += self.c_strlen(string) | |
| 34 return result | |
| 35 | |
| 36 def writeDefinition(self, f, name): | |
| 37 entries = self.table.items() | |
| 38 entries.sort(key=lambda x:x[1]) | |
| 39 # Avoid null-in-string warnings with GCC and potentially | |
| 40 # overlong string constants; write everything out the long way. | |
| 41 def explodeToCharArray(string): | |
| 42 def toCChar(s): | |
| 43 if s == "'": | |
| 44 return "'\\''" | |
| 45 else: | |
| 46 return "'%s'" % s | |
| 47 return ", ".join(map(toCChar, string)) | |
| 48 f.write("const char %s[] = {\n" % name) | |
| 49 for (string, offset) in entries[:-1]: | |
| 50 e = explodeToCharArray(string) | |
| 51 if e: | |
| 52 f.write(" /* %5d */ %s, '\\0',\n" | |
| 53 % (offset, explodeToCharArray(string))) | |
| 54 else: | |
| 55 f.write(" /* %5d */ '\\0',\n" % offset) | |
| 56 f.write(" /* %5d */ %s, '\\0' };\n\n" | |
| 57 % (entries[-1][1], explodeToCharArray(entries[-1][0]))) | |
| 58 | |
| 59 def print_array_entry(histogram, name_index, exp_index): | |
| 60 cpp_guard = histogram.cpp_guard() | |
| 61 if cpp_guard: | |
| 62 print "#if defined(%s)" % cpp_guard | |
| 63 print " { %s, %s, %s, %s, %d, %d, %s }," \ | |
| 64 % (histogram.low(), histogram.high(), | |
| 65 histogram.n_buckets(), histogram.nsITelemetry_kind(), | |
| 66 name_index, exp_index, | |
| 67 "true" if histogram.extended_statistics_ok() else "false") | |
| 68 if cpp_guard: | |
| 69 print "#endif" | |
| 70 | |
| 71 def write_histogram_table(histograms): | |
| 72 table = StringTable() | |
| 73 | |
| 74 print "const TelemetryHistogram gHistograms[] = {" | |
| 75 for histogram in histograms: | |
| 76 name_index = table.stringIndex(histogram.name()) | |
| 77 exp_index = table.stringIndex(histogram.expiration()) | |
| 78 print_array_entry(histogram, name_index, exp_index) | |
| 79 print "};" | |
| 80 | |
| 81 strtab_name = "gHistogramStringTable" | |
| 82 table.writeDefinition(sys.stdout, strtab_name) | |
| 83 static_assert("sizeof(%s) <= UINT32_MAX" % strtab_name, | |
| 84 "index overflow") | |
| 85 | |
| 86 # Write out static asserts for histogram data. We'd prefer to perform | |
| 87 # these checks in this script itself, but since several histograms | |
| 88 # (generally enumerated histograms) use compile-time constants for | |
| 89 # their upper bounds, we have to let the compiler do the checking. | |
| 90 | |
| 91 def static_assert(expression, message): | |
| 92 print "static_assert(%s, \"%s\");" % (expression, message) | |
| 93 | |
| 94 def static_asserts_for_boolean(histogram): | |
| 95 pass | |
| 96 | |
| 97 def static_asserts_for_flag(histogram): | |
| 98 pass | |
| 99 | |
| 100 def static_asserts_for_enumerated(histogram): | |
| 101 n_values = histogram.high() | |
| 102 static_assert("%s > 2" % n_values, | |
| 103 "Not enough values for %s" % histogram.name()) | |
| 104 | |
| 105 def shared_static_asserts(histogram): | |
| 106 name = histogram.name() | |
| 107 low = histogram.low() | |
| 108 high = histogram.high() | |
| 109 n_buckets = histogram.n_buckets() | |
| 110 static_assert("%s < %s" % (low, high), "low >= high for %s" % name) | |
| 111 static_assert("%s > 2" % n_buckets, "Not enough values for %s" % name) | |
| 112 static_assert("%s >= 1" % low, "Incorrect low value for %s" % name) | |
| 113 static_assert("%s > %s" % (high, n_buckets), | |
| 114 "high must be > number of buckets for %s; you may want an enumerated histogram" % name) | |
| 115 | |
| 116 def static_asserts_for_linear(histogram): | |
| 117 shared_static_asserts(histogram) | |
| 118 | |
| 119 def static_asserts_for_exponential(histogram): | |
| 120 shared_static_asserts(histogram) | |
| 121 | |
| 122 def write_histogram_static_asserts(histograms): | |
| 123 print """ | |
| 124 // Perform the checks at the beginning of HistogramGet at | |
| 125 // compile time, so that incorrect histogram definitions | |
| 126 // give compile-time errors, not runtime errors.""" | |
| 127 | |
| 128 table = { | |
| 129 'boolean' : static_asserts_for_boolean, | |
| 130 'flag' : static_asserts_for_flag, | |
| 131 'enumerated' : static_asserts_for_enumerated, | |
| 132 'linear' : static_asserts_for_linear, | |
| 133 'exponential' : static_asserts_for_exponential, | |
| 134 } | |
| 135 | |
| 136 for histogram in histograms: | |
| 137 histogram_tools.table_dispatch(histogram.kind(), table, | |
| 138 lambda f: f(histogram)) | |
| 139 | |
| 140 def write_debug_histogram_ranges(histograms): | |
| 141 ranges_lengths = [] | |
| 142 | |
| 143 # Collect all the range information from individual histograms. | |
| 144 # Write that information out as well. | |
| 145 print "#ifdef DEBUG" | |
| 146 print "const int gBucketLowerBounds[] = {" | |
| 147 for histogram in histograms: | |
| 148 ranges = [] | |
| 149 try: | |
| 150 ranges = histogram.ranges() | |
| 151 except histogram_tools.DefinitionException: | |
| 152 pass | |
| 153 ranges_lengths.append(len(ranges)) | |
| 154 # Note that we do not test cpp_guard here. We do this so we | |
| 155 # will have complete information about all the histograms in | |
| 156 # this array. Just having information about the ranges of | |
| 157 # histograms is not platform-specific; if there are histograms | |
| 158 # that have platform-specific constants in their definitions, | |
| 159 # those histograms will fail in the .ranges() call above and | |
| 160 # we'll have a zero-length array to deal with here. | |
| 161 if len(ranges) > 0: | |
| 162 print ','.join(map(str, ranges)), ',' | |
| 163 else: | |
| 164 print '/* Skipping %s */' % histogram.name() | |
| 165 print "};" | |
| 166 | |
| 167 # Write the offsets into gBucketLowerBounds. | |
| 168 print "struct bounds { int offset; int length; };" | |
| 169 print "const struct bounds gBucketLowerBoundIndex[] = {" | |
| 170 offset = 0 | |
| 171 for (histogram, range_length) in itertools.izip(histograms, ranges_lengths): | |
| 172 cpp_guard = histogram.cpp_guard() | |
| 173 # We do test cpp_guard here, so that histogram IDs are valid | |
| 174 # indexes into this array. | |
| 175 if cpp_guard: | |
| 176 print "#if defined(%s)" % cpp_guard | |
| 177 print "{ %d, %d }," % (offset, range_length) | |
| 178 if cpp_guard: | |
| 179 print "#endif" | |
| 180 offset += range_length | |
| 181 print "};" | |
| 182 print "#endif" | |
| 183 | |
| 184 def main(argv): | |
| 185 filename = argv[0] | |
| 186 | |
| 187 histograms = list(histogram_tools.from_file(filename)) | |
| 188 | |
| 189 print banner | |
| 190 write_histogram_table(histograms) | |
| 191 write_histogram_static_asserts(histograms) | |
| 192 write_debug_histogram_ranges(histograms) | |
| 193 | |
| 194 main(sys.argv[1:]) |
