From 9fe1d9ac6820cff354a5402114b96dae1221eba3 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Sun, 26 Apr 2015 18:02:32 +0200 Subject: [PATCH] Fix possible division by zero in pg_xlogdump. When displaying stats it was possible that a floating point division by zero occured when no FPIs were issued for a type of record. Author: Abhijit Menon-Sen Discussion: 20150417091811.GA14008@toroid.org --- src/bin/pg_xlogdump/pg_xlogdump.c | 53 ++++++++++++++++++++++--------- 1 file changed, 38 insertions(+), 15 deletions(-) diff --git a/src/bin/pg_xlogdump/pg_xlogdump.c b/src/bin/pg_xlogdump/pg_xlogdump.c index d634807eb5..e9cbbd264d 100644 --- a/src/bin/pg_xlogdump/pg_xlogdump.c +++ b/src/bin/pg_xlogdump/pg_xlogdump.c @@ -489,18 +489,36 @@ XLogDumpDisplayRecord(XLogDumpConfig *config, XLogReaderState *record) */ static void XLogDumpStatsRow(const char *name, - uint64 n, double n_pct, - uint64 rec_len, double rec_len_pct, - uint64 fpi_len, double fpi_len_pct, - uint64 total_len, double total_len_pct) + uint64 n, uint64 total_count, + uint64 rec_len, uint64 total_rec_len, + uint64 fpi_len, uint64 total_fpi_len, + uint64 tot_len, uint64 total_len) { + double n_pct, rec_len_pct, fpi_len_pct, tot_len_pct; + + n_pct = 0; + if (total_count != 0) + n_pct = 100 * (double) n / total_count; + + rec_len_pct = 0; + if (total_rec_len != 0) + rec_len_pct = 100 * (double) rec_len / total_rec_len; + + fpi_len_pct = 0; + if (total_fpi_len != 0) + fpi_len_pct = 100 * (double) fpi_len / total_fpi_len; + + tot_len_pct = 0; + if (total_len != 0) + tot_len_pct = 100 * (double) tot_len / total_len; + printf("%-27s " "%20" INT64_MODIFIER "u (%6.02f) " "%20" INT64_MODIFIER "u (%6.02f) " "%20" INT64_MODIFIER "u (%6.02f) " "%20" INT64_MODIFIER "u (%6.02f)\n", name, n, n_pct, rec_len, rec_len_pct, fpi_len, fpi_len_pct, - total_len, total_len_pct); + tot_len, tot_len_pct); } @@ -515,6 +533,7 @@ XLogDumpDisplayStats(XLogDumpConfig *config, XLogDumpStats *stats) uint64 total_rec_len = 0; uint64 total_fpi_len = 0; uint64 total_len = 0; + double rec_len_pct, fpi_len_pct; /* --- * Make a first pass to calculate column totals: @@ -557,10 +576,8 @@ XLogDumpDisplayStats(XLogDumpConfig *config, XLogDumpStats *stats) tot_len = rec_len + fpi_len; XLogDumpStatsRow(desc->rm_name, - count, 100 * (double) count / total_count, - rec_len, 100 * (double) rec_len / total_rec_len, - fpi_len, 100 * (double) fpi_len / total_fpi_len, - tot_len, 100 * (double) tot_len / total_len); + count, total_count, rec_len, total_rec_len, + fpi_len, total_fpi_len, tot_len, total_len); } else { @@ -583,10 +600,8 @@ XLogDumpDisplayStats(XLogDumpConfig *config, XLogDumpStats *stats) id = psprintf("UNKNOWN (%x)", rj << 4); XLogDumpStatsRow(psprintf("%s/%s", desc->rm_name, id), - count, 100 * (double) count / total_count, - rec_len, 100 * (double) rec_len / total_rec_len, - fpi_len, 100 * (double) fpi_len / total_fpi_len, - tot_len, 100 * (double) tot_len / total_len); + count, total_count, rec_len, total_rec_len, + fpi_len, total_fpi_len, tot_len, total_len); } } } @@ -601,14 +616,22 @@ XLogDumpDisplayStats(XLogDumpConfig *config, XLogDumpStats *stats) * them from the earlier ones, and are thus up to 9 characters long. */ + rec_len_pct = 0; + if (total_len != 0) + rec_len_pct = 100 * (double) total_rec_len / total_len; + + fpi_len_pct = 0; + if (total_len != 0) + fpi_len_pct = 100 * (double) total_fpi_len / total_len; + printf("%-27s " "%20" INT64_MODIFIER "u %-9s" "%20" INT64_MODIFIER "u %-9s" "%20" INT64_MODIFIER "u %-9s" "%20" INT64_MODIFIER "u %-6s\n", "Total", stats->count, "", - total_rec_len, psprintf("[%.02f%%]", 100 * (double)total_rec_len / total_len), - total_fpi_len, psprintf("[%.02f%%]", 100 * (double)total_fpi_len / total_len), + total_rec_len, psprintf("[%.02f%%]", rec_len_pct), + total_fpi_len, psprintf("[%.02f%%]", fpi_len_pct), total_len, "[100%]"); } -- 2.40.0