From 75cc66f26344aa95c916ba580191e3d17fa817c2 Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Tue, 16 Aug 2016 16:14:18 +0200 Subject: gcov: add new option (--hash-filenames) (PR PR gcov-profile/36412 * doc/gcov.texi: Document --hash-filenames(-x). * gcov.c (print_usage): Add the option. (process_args): Process the option, sort options alphabetically. (md5sum_to_hex): New function. (make_gcov_file_name): Do the md5sum and append it to a filename. From-SVN: r239503 --- gcc/ChangeLog | 10 ++++++++++ gcc/doc/gcov.texi | 11 +++++++++++ gcc/gcov.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++-- 3 files changed, 67 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index e2d39a8..df13320 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2016-08-16 Martin Liska + + PR gcov-profile/36412 + * doc/gcov.texi: Document --hash-filenames(-x). + * gcov.c (print_usage): Add the option. + (process_args): Process the option, sort options alphabetically. + (md5sum_to_hex): New function. + (make_gcov_file_name): Do the md5sum and append it to a + filename. + 2016-08-16 Bin Cheng PR tree-optimization/69848 diff --git a/gcc/doc/gcov.texi b/gcc/doc/gcov.texi index df58df8..a0a7af7 100644 --- a/gcc/doc/gcov.texi +++ b/gcc/doc/gcov.texi @@ -133,6 +133,7 @@ gcov [@option{-v}|@option{--version}] [@option{-h}|@option{--help}] [@option{-r}|@option{--relative-only}] [@option{-s}|@option{--source-prefix} @var{directory}] [@option{-u}|@option{--unconditional-branches}] + [@option{-x}|@option{--hash-filenames}] @var{files} @c man end @c man begin SEEALSO @@ -278,6 +279,16 @@ branch:28,nottaken Display demangled function names in output. The default is to show mangled function names. +@item -x +@itemx --hash-filenames +By default, gcov uses the full pathname of the source files to to create +an output filename. This can lead to long filenames that can overflow +filesystem limits. This option creates names of the form +@file{@var{source-file}##@var{md5}.gcov}, +where the @var{source-file} component is the final filename part and +the @var{md5} component is calculated from the full mangled name that +would have been used otherwise. + @end table @command{gcov} should be run with the current directory the same as that diff --git a/gcc/gcov.c b/gcc/gcov.c index 30fc167..da0bc97 100644 --- a/gcc/gcov.c +++ b/gcc/gcov.c @@ -43,6 +43,7 @@ along with Gcov; see the file COPYING3. If not see #include #include +#include "md5.h" using namespace std; @@ -359,6 +360,11 @@ static int flag_demangled_names = 0; static int flag_long_names = 0; +/* For situations when a long name can potentially hit filesystem path limit, + let's calculate md5sum of the path and append it to a file name. */ + +static int flag_hash_filenames = 0; + /* Output count information for every basic block, not merely those that contain line number information. */ @@ -667,6 +673,7 @@ print_usage (int error_p) fnotice (file, " -s, --source-prefix DIR Source prefix to elide\n"); fnotice (file, " -u, --unconditional-branches Show unconditional branch counts too\n"); fnotice (file, " -v, --version Print version number, then exit\n"); + fnotice (file, " -x, --hash-filenames Hash long pathnames\n"); fnotice (file, "\nFor bug reporting instructions, please see:\n%s.\n", bug_report_url); exit (status); @@ -706,6 +713,7 @@ static const struct option options[] = { "source-prefix", required_argument, NULL, 's' }, { "unconditional-branches", no_argument, NULL, 'u' }, { "display-progress", no_argument, NULL, 'd' }, + { "hash-filenames", no_argument, NULL, 'x' }, { 0, 0, 0, 0 } }; @@ -716,8 +724,8 @@ process_args (int argc, char **argv) { int opt; - while ((opt = getopt_long (argc, argv, "abcdfhilmno:s:pruv", options, NULL)) != - -1) + const char *opts = "abcdfhilmno:prs:uvx"; + while ((opt = getopt_long (argc, argv, opts, options, NULL)) != -1) { switch (opt) { @@ -770,6 +778,9 @@ process_args (int argc, char **argv) break; case 'v': print_version (); + case 'x': + flag_hash_filenames = 1; + break; /* print_version will exit. */ default: print_usage (true); @@ -2147,6 +2158,15 @@ canonicalize_name (const char *name) return result; } +/* Print hex representation of 16 bytes from SUM and write it to BUFFER. */ + +static void +md5sum_to_hex (const char *sum, char *buffer) +{ + for (unsigned i = 0; i < 16; i++) + sprintf (buffer + (2 * i), "%02x", sum[i]); +} + /* Generate an output file name. INPUT_NAME is the canonicalized main input file and SRC_NAME is the canonicalized file name. LONG_OUTPUT_NAMES and PRESERVE_PATHS affect name generation. With @@ -2184,6 +2204,30 @@ make_gcov_file_name (const char *input_name, const char *src_name) ptr = mangle_name (src_name, ptr); strcpy (ptr, ".gcov"); + /* When hashing filenames, we shorten them by only using the filename + component and appending a hash of the full (mangled) pathname. */ + if (flag_hash_filenames) + { + md5_ctx ctx; + char md5sum[16]; + char md5sum_hex[33]; + + md5_init_ctx (&ctx); + md5_process_bytes (result, strlen (result), &ctx); + md5_finish_ctx (&ctx, md5sum); + md5sum_to_hex (md5sum, md5sum_hex); + free (result); + + result = XNEWVEC (char, strlen (src_name) + 50); + ptr = result; + ptr = mangle_name (src_name, ptr); + ptr[0] = ptr[1] = '#'; + ptr += 2; + memcpy (ptr, md5sum_hex, 32); + ptr += 32; + strcpy (ptr, ".gcov"); + } + return result; } -- cgit v1.1