diff options
Diffstat (limited to 'src/backend/utils/misc/ps_status.c')
| -rw-r--r-- | src/backend/utils/misc/ps_status.c | 37 |
1 files changed, 15 insertions, 22 deletions
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c index 8d34d235815..518e4a8aa46 100644 --- a/src/backend/utils/misc/ps_status.c +++ b/src/backend/utils/misc/ps_status.c @@ -5,7 +5,7 @@ * to contain some useful information. Mechanism differs wildly across * platforms. * - * $PostgreSQL: pgsql/src/backend/utils/misc/ps_status.c,v 1.23.4.1 2005/11/05 03:05:05 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/misc/ps_status.c,v 1.23.4.2 2010/05/27 19:20:16 tgl Exp $ * * Copyright (c) 2000-2005, PostgreSQL Global Development Group * various details abducted from various places @@ -89,8 +89,11 @@ static const size_t ps_buffer_size = PS_BUFFER_SIZE; #else /* PS_USE_CLOBBER_ARGV */ static char *ps_buffer; /* will point to argv area */ static size_t ps_buffer_size; /* space determined at run time */ +static size_t last_status_len; /* use to minimize length of clobber */ #endif /* PS_USE_CLOBBER_ARGV */ +static size_t ps_buffer_cur_len; /* nominal strlen(ps_buffer) */ + static size_t ps_buffer_fixed_size; /* size of the constant prefix */ /* save the original argv[] location here */ @@ -173,7 +176,7 @@ save_ps_display_args(int argc, char **argv) } ps_buffer = argv[0]; - ps_buffer_size = end_of_area - argv[0]; + last_status_len = ps_buffer_size = end_of_area - argv[0]; /* * move the environment out of the way @@ -290,7 +293,7 @@ init_ps_display(const char *username, const char *dbname, username, dbname, host_info); #endif - ps_buffer_fixed_size = strlen(ps_buffer); + ps_buffer_cur_len = ps_buffer_fixed_size = strlen(ps_buffer); #ifdef WIN32 pgwin32_update_ident(ps_buffer); @@ -322,6 +325,7 @@ set_ps_display(const char *activity) /* Update ps_buffer to contain both fixed part and activity */ StrNCpy(ps_buffer + ps_buffer_fixed_size, activity, ps_buffer_size - ps_buffer_fixed_size); + ps_buffer_cur_len = strlen(ps_buffer); /* Transmit new setting to kernel, if necessary */ @@ -334,7 +338,7 @@ set_ps_display(const char *activity) union pstun pst; pst.pst_command = ps_buffer; - pstat(PSTAT_SETCMD, pst, strlen(ps_buffer), 0, 0); + pstat(PSTAT_SETCMD, pst, ps_buffer_cur_len, 0, 0); } #endif /* PS_USE_PSTAT */ @@ -344,13 +348,11 @@ set_ps_display(const char *activity) #endif /* PS_USE_PS_STRINGS */ #ifdef PS_USE_CLOBBER_ARGV - { - int buflen; - - /* pad unused memory */ - buflen = strlen(ps_buffer); - MemSet(ps_buffer + buflen, PS_PADDING, ps_buffer_size - buflen); - } + /* pad unused memory; need only clobber remainder of old status string */ + if (last_status_len > ps_buffer_cur_len) + MemSet(ps_buffer + ps_buffer_cur_len, PS_PADDING, + last_status_len - ps_buffer_cur_len); + last_status_len = ps_buffer_cur_len; #endif /* PS_USE_CLOBBER_ARGV */ #ifdef WIN32 @@ -371,24 +373,15 @@ const char * get_ps_display(int *displen) { #ifdef PS_USE_CLOBBER_ARGV - size_t offset; - /* If ps_buffer is a pointer, it might still be null */ if (!ps_buffer) { *displen = 0; return ""; } - - /* Remove any trailing spaces to offset the effect of PS_PADDING */ - offset = ps_buffer_size; - while (offset > ps_buffer_fixed_size && ps_buffer[offset-1] == PS_PADDING) - offset--; - - *displen = offset - ps_buffer_fixed_size; -#else - *displen = strlen(ps_buffer + ps_buffer_fixed_size); #endif + *displen = (int) (ps_buffer_cur_len - ps_buffer_fixed_size); + return ps_buffer + ps_buffer_fixed_size; } |