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tool: improve --stderr handling

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- freopen stderr with the user-specified file (--stderr file) instead of
  using a separate 'errors' stream.

- In tool_setup.h override stdio.h's stderr macro as global variable
  tool_stderr.

Both freopen and overriding the stderr macro are necessary because if
the user-specified filename is "-" then stdout is assigned to
tool_stderr and no freopen takes place. See the PR for more information.

Ref: https://github.com/curl/curl/issues/10491

Closes https://github.com/curl/curl/pull/10673
This commit is contained in:
Jay Satiro 2023-03-04 04:07:24 -05:00
parent 395b9175b7
commit 2f17a9b654
14 changed files with 151 additions and 60 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/Makefile.inc
View File

@ -82,6 +82,7 @@ CURL_CFILES = \
tool_paramhlp.c \ tool_paramhlp.c \
tool_parsecfg.c \ tool_parsecfg.c \
tool_progress.c \ tool_progress.c \
tool_stderr.c \
tool_strdup.c \ tool_strdup.c \
tool_setopt.c \ tool_setopt.c \
tool_sleep.c \ tool_sleep.c \
@ -126,6 +127,7 @@ CURL_HFILES = \
tool_setopt.h \ tool_setopt.h \
tool_setup.h \ tool_setup.h \
tool_sleep.h \ tool_sleep.h \
tool_stderr.h \
tool_strdup.h \ tool_strdup.h \
tool_urlglob.h \ tool_urlglob.h \
tool_util.h \ tool_util.h \

4
src/tool_cb_dbg.c
View File

@ -48,7 +48,7 @@ int tool_debug_cb(CURL *handle, curl_infotype type,
{ {
struct OperationConfig *operation = userdata; struct OperationConfig *operation = userdata;
struct GlobalConfig *config = operation->global; struct GlobalConfig *config = operation->global;
FILE *output = config->errors; FILE *output = stderr;
const char *text; const char *text;
struct timeval tv; struct timeval tv;
char timebuf[20]; char timebuf[20];
@ -80,7 +80,7 @@ int tool_debug_cb(CURL *handle, curl_infotype type,
config->trace_stream = stdout; config->trace_stream = stdout;
else if(!strcmp("%", config->trace_dump)) else if(!strcmp("%", config->trace_dump))
/* Ok, this is somewhat hackish but we do it undocumented for now */ /* Ok, this is somewhat hackish but we do it undocumented for now */
config->trace_stream = config->errors; /* aka stderr */ config->trace_stream = stderr;
else { else {
config->trace_stream = fopen(config->trace_dump, FOPEN_WRITETEXT); config->trace_stream = fopen(config->trace_dump, FOPEN_WRITETEXT);
config->trace_fopened = TRUE; config->trace_fopened = TRUE;

2
src/tool_cb_prg.c
View File

@ -274,7 +274,7 @@ void progressbarinit(struct ProgressData *bar,
else if(bar->width > MAX_BARLENGTH) else if(bar->width > MAX_BARLENGTH)
bar->width = MAX_BARLENGTH; bar->width = MAX_BARLENGTH;
bar->out = config->global->errors; bar->out = stderr;
bar->tick = 150; bar->tick = 150;
bar->barmove = 1; bar->barmove = 1;
} }

2
src/tool_cfgable.h
View File

@ -302,8 +302,6 @@ struct GlobalConfig {
bool silent; /* don't show messages, --silent given */ bool silent; /* don't show messages, --silent given */
bool noprogress; /* don't show progress bar */ bool noprogress; /* don't show progress bar */
bool isatty; /* Updated internally if output is a tty */ bool isatty; /* Updated internally if output is a tty */
FILE *errors; /* Error stream, defaults to stderr */
bool errors_fopened; /* Whether error stream isn't stderr */
char *trace_dump; /* file to dump the network trace to */ char *trace_dump; /* file to dump the network trace to */
FILE *trace_stream; FILE *trace_stream;
bool trace_fopened; bool trace_fopened;

9
src/tool_formparse.c
View File

@ -417,8 +417,7 @@ static int read_field_headers(struct OperationConfig *config,
if(hdrlen) { if(hdrlen) {
hdrbuf[hdrlen] = '\0'; hdrbuf[hdrlen] = '\0';
if(slist_append(pheaders, hdrbuf)) { if(slist_append(pheaders, hdrbuf)) {
fprintf(config->global->errors, fprintf(stderr, "Out of memory for field headers!\n");
"Out of memory for field headers!\n");
return -1; return -1;
} }
hdrlen = 0; hdrlen = 0;
@ -428,8 +427,8 @@ static int read_field_headers(struct OperationConfig *config,
switch(c) { switch(c) {
case EOF: case EOF:
if(ferror(fp)) { if(ferror(fp)) {
fprintf(config->global->errors, fprintf(stderr, "Header file %s read error: %s\n", filename,
"Header file %s read error: %s\n", filename, strerror(errno)); strerror(errno));
return -1; return -1;
} }
return 0; /* Done. */ return 0; /* Done. */
@ -585,7 +584,7 @@ static int get_param_part(struct OperationConfig *config, char endchar,
sep = *p; sep = *p;
*endpos = '\0'; *endpos = '\0';
if(slist_append(&headers, hdr)) { if(slist_append(&headers, hdr)) {
fprintf(config->global->errors, "Out of memory for field header!\n"); fprintf(stderr, "Out of memory for field header!\n");
curl_slist_free_all(headers); curl_slist_free_all(headers);
return -1; return -1;
} }

19
src/tool_getparam.c
View File

@ -42,6 +42,7 @@
#include "tool_parsecfg.h" #include "tool_parsecfg.h"
#include "tool_main.h" #include "tool_main.h"
#include "dynbuf.h" #include "dynbuf.h"
#include "tool_stderr.h"
#include "memdebug.h" /* keep this as LAST include */ #include "memdebug.h" /* keep this as LAST include */
@ -1036,19 +1037,7 @@ ParameterError getparameter(const char *flag, /* f or -long-flag */
break; break;
case 'v': /* --stderr */ case 'v': /* --stderr */
if(strcmp(nextarg, "-")) { tool_set_stderr_file(nextarg);
FILE *newfile = fopen(nextarg, FOPEN_WRITETEXT);
if(!newfile)
warnf(global, "Failed to open %s!\n", nextarg);
else {
if(global->errors_fopened)
fclose(global->errors);
global->errors = newfile;
global->errors_fopened = TRUE;
}
}
else
global->errors = stdout;
break; break;
case 'w': /* --interface */ case 'w': /* --interface */
/* interface */ /* interface */
@ -2567,9 +2556,9 @@ ParameterError parse_args(struct GlobalConfig *global, int argc,
const char *reason = param2text(result); const char *reason = param2text(result);
if(orig_opt && strcmp(":", orig_opt)) if(orig_opt && strcmp(":", orig_opt))
helpf(global->errors, "option %s: %s\n", orig_opt, reason); helpf(stderr, "option %s: %s\n", orig_opt, reason);
else else
helpf(global->errors, "%s\n", reason); helpf(stderr, "%s\n", reason);
} }
curlx_unicodefree(orig_opt); curlx_unicodefree(orig_opt);

8
src/tool_main.c
View File

@ -53,6 +53,7 @@
#include "tool_vms.h" #include "tool_vms.h"
#include "tool_main.h" #include "tool_main.h"
#include "tool_libinfo.h" #include "tool_libinfo.h"
#include "tool_stderr.h"
/* /*
* This is low-level hard-hacking memory leak tracking and similar. Using * This is low-level hard-hacking memory leak tracking and similar. Using
@ -156,7 +157,6 @@ static CURLcode main_init(struct GlobalConfig *config)
/* Initialise the global config */ /* Initialise the global config */
config->showerror = FALSE; /* show errors when silent */ config->showerror = FALSE; /* show errors when silent */
config->errors = stderr; /* Default errors to stderr */
config->styled_output = TRUE; /* enable detection */ config->styled_output = TRUE; /* enable detection */
config->parallel_max = PARALLEL_DEFAULT; config->parallel_max = PARALLEL_DEFAULT;
@ -196,10 +196,6 @@ static void free_globalconfig(struct GlobalConfig *config)
{ {
Curl_safefree(config->trace_dump); Curl_safefree(config->trace_dump);
if(config->errors_fopened && config->errors)
fclose(config->errors);
config->errors = NULL;
if(config->trace_fopened && config->trace_stream) if(config->trace_fopened && config->trace_stream)
fclose(config->trace_stream); fclose(config->trace_stream);
config->trace_stream = NULL; config->trace_stream = NULL;
@ -250,6 +246,8 @@ int main(int argc, char *argv[])
struct GlobalConfig global; struct GlobalConfig global;
memset(&global, 0, sizeof(global)); memset(&global, 0, sizeof(global));
tool_init_stderr();
#ifdef WIN32 #ifdef WIN32
/* Undocumented diagnostic option to list the full paths of all loaded /* Undocumented diagnostic option to list the full paths of all loaded
modules. This is purposely pre-init. */ modules. This is purposely pre-init. */

8
src/tool_msgs.c
View File

@ -54,7 +54,7 @@ static void voutf(struct GlobalConfig *config,
ptr = print_buffer; ptr = print_buffer;
while(len > 0) { while(len > 0) {
fputs(prefix, config->errors); fputs(prefix, stderr);
if(len > width) { if(len > width) {
size_t cut = width-1; size_t cut = width-1;
@ -67,13 +67,13 @@ static void voutf(struct GlobalConfig *config,
max text width then! */ max text width then! */
cut = width-1; cut = width-1;
(void)fwrite(ptr, cut + 1, 1, config->errors); (void)fwrite(ptr, cut + 1, 1, stderr);
fputs("\n", config->errors); fputs("\n", stderr);
ptr += cut + 1; /* skip the space too */ ptr += cut + 1; /* skip the space too */
len -= cut + 1; len -= cut + 1;
} }
else { else {
fputs(ptr, config->errors); fputs(ptr, stderr);
len = 0; len = 0;
} }
} }

39
src/tool_operate.c
View File

@ -306,7 +306,7 @@ static CURLcode pre_transfer(struct GlobalConfig *global,
if((per->infd == -1) || fstat(per->infd, &fileinfo)) if((per->infd == -1) || fstat(per->infd, &fileinfo))
#endif #endif
{ {
helpf(global->errors, "Can't open '%s'!\n", per->uploadfile); helpf(stderr, "Can't open '%s'!\n", per->uploadfile);
if(per->infd != -1) { if(per->infd != -1) {
close(per->infd); close(per->infd);
per->infd = STDIN_FILENO; per->infd = STDIN_FILENO;
@ -404,10 +404,10 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
if(!config->synthetic_error && result && if(!config->synthetic_error && result &&
(!global->silent || global->showerror)) { (!global->silent || global->showerror)) {
const char *msg = per->errorbuffer; const char *msg = per->errorbuffer;
fprintf(global->errors, "curl: (%d) %s\n", result, fprintf(stderr, "curl: (%d) %s\n", result,
(msg && msg[0]) ? msg : curl_easy_strerror(result)); (msg && msg[0]) ? msg : curl_easy_strerror(result));
if(result == CURLE_PEER_FAILED_VERIFICATION) if(result == CURLE_PEER_FAILED_VERIFICATION)
fputs(CURL_CA_CERT_ERRORMSG, global->errors); fputs(CURL_CA_CERT_ERRORMSG, stderr);
} }
else if(config->failwithbody) { else if(config->failwithbody) {
/* if HTTP response >= 400, return error */ /* if HTTP response >= 400, return error */
@ -415,7 +415,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &code); curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &code);
if(code >= 400) { if(code >= 400) {
if(!global->silent || global->showerror) if(!global->silent || global->showerror)
fprintf(global->errors, fprintf(stderr,
"curl: (%d) The requested URL returned error: %ld\n", "curl: (%d) The requested URL returned error: %ld\n",
CURLE_HTTP_RETURNED_ERROR, code); CURLE_HTTP_RETURNED_ERROR, code);
result = CURLE_HTTP_RETURNED_ERROR; result = CURLE_HTTP_RETURNED_ERROR;
@ -448,7 +448,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
/* something went wrong in the writing process */ /* something went wrong in the writing process */
result = CURLE_WRITE_ERROR; result = CURLE_WRITE_ERROR;
if(!global->silent || global->showerror) if(!global->silent || global->showerror)
fprintf(global->errors, "curl: (%d) Failed writing body\n", result); fprintf(stderr, "curl: (%d) Failed writing body\n", result);
} }
} }
@ -589,8 +589,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
/* We have written data to an output file, we truncate file /* We have written data to an output file, we truncate file
*/ */
if(!global->silent) if(!global->silent)
fprintf(global->errors, "Throwing away %" fprintf(stderr, "Throwing away %" CURL_FORMAT_CURL_OFF_T " bytes\n",
CURL_FORMAT_CURL_OFF_T " bytes\n",
outs->bytes); outs->bytes);
fflush(outs->stream); fflush(outs->stream);
/* truncate file at the position where we started appending */ /* truncate file at the position where we started appending */
@ -599,8 +598,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
/* when truncate fails, we can't just append as then we'll /* when truncate fails, we can't just append as then we'll
create something strange, bail out */ create something strange, bail out */
if(!global->silent || global->showerror) if(!global->silent || global->showerror)
fprintf(global->errors, fprintf(stderr, "curl: (23) Failed to truncate file\n");
"curl: (23) Failed to truncate file\n");
return CURLE_WRITE_ERROR; return CURLE_WRITE_ERROR;
} }
/* now seek to the end of the file, the position where we /* now seek to the end of the file, the position where we
@ -615,8 +613,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
#endif #endif
if(rc) { if(rc) {
if(!global->silent || global->showerror) if(!global->silent || global->showerror)
fprintf(global->errors, fprintf(stderr, "curl: (23) Failed seeking to end of file\n");
"curl: (23) Failed seeking to end of file\n");
return CURLE_WRITE_ERROR; return CURLE_WRITE_ERROR;
} }
outs->bytes = 0; /* clear for next round */ outs->bytes = 0; /* clear for next round */
@ -641,7 +638,7 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
/* something went wrong in the writing process */ /* something went wrong in the writing process */
result = CURLE_WRITE_ERROR; result = CURLE_WRITE_ERROR;
if(!global->silent || global->showerror) if(!global->silent || global->showerror)
fprintf(global->errors, "curl: (%d) Failed writing body\n", result); fprintf(stderr, "curl: (%d) Failed writing body\n", result);
} }
if(result && config->rm_partial) { if(result && config->rm_partial) {
notef(global, "Removing output file: %s\n", outs->filename); notef(global, "Removing output file: %s\n", outs->filename);
@ -801,7 +798,7 @@ static CURLcode single_transfer(struct GlobalConfig *global,
/* Unless explicitly shut off */ /* Unless explicitly shut off */
result = glob_url(&inglob, infiles, &state->infilenum, result = glob_url(&inglob, infiles, &state->infilenum,
(!global->silent || global->showerror)? (!global->silent || global->showerror)?
global->errors:NULL); stderr:NULL);
if(result) if(result)
break; break;
config->state.inglob = inglob; config->state.inglob = inglob;
@ -837,7 +834,7 @@ static CURLcode single_transfer(struct GlobalConfig *global,
expressions and return total number of URLs in pattern set */ expressions and return total number of URLs in pattern set */
result = glob_url(&state->urls, urlnode->url, &state->urlnum, result = glob_url(&state->urls, urlnode->url, &state->urlnum,
(!global->silent || global->showerror)? (!global->silent || global->showerror)?
global->errors:NULL); stderr:NULL);
if(result) if(result)
break; break;
urlnum = state->urlnum; urlnum = state->urlnum;
@ -1096,7 +1093,7 @@ static CURLcode single_transfer(struct GlobalConfig *global,
file output call */ file output call */
if(config->create_dirs) { if(config->create_dirs) {
result = create_dir_hierarchy(per->outfile, global->errors); result = create_dir_hierarchy(per->outfile, stderr);
/* create_dir_hierarchy shows error upon CURLE_WRITE_ERROR */ /* create_dir_hierarchy shows error upon CURLE_WRITE_ERROR */
if(result) if(result)
break; break;
@ -1240,9 +1237,6 @@ static CURLcode single_transfer(struct GlobalConfig *global,
} }
} }
if(!global->errors)
global->errors = stderr;
if((!per->outfile || !strcmp(per->outfile, "-")) && if((!per->outfile || !strcmp(per->outfile, "-")) &&
!config->use_ascii) { !config->use_ascii) {
/* We get the output to stdout and we have not got the ASCII/text /* We get the output to stdout and we have not got the ASCII/text
@ -1851,7 +1845,7 @@ static CURLcode single_transfer(struct GlobalConfig *global,
my_setopt(curl, CURLOPT_TIMEVALUE_LARGE, config->condtime); my_setopt(curl, CURLOPT_TIMEVALUE_LARGE, config->condtime);
my_setopt_str(curl, CURLOPT_CUSTOMREQUEST, config->customrequest); my_setopt_str(curl, CURLOPT_CUSTOMREQUEST, config->customrequest);
customrequest_helper(config, config->httpreq, config->customrequest); customrequest_helper(config, config->httpreq, config->customrequest);
my_setopt(curl, CURLOPT_STDERR, global->errors); my_setopt(curl, CURLOPT_STDERR, stderr);
/* three new ones in libcurl 7.3: */ /* three new ones in libcurl 7.3: */
my_setopt_str(curl, CURLOPT_INTERFACE, config->iface); my_setopt_str(curl, CURLOPT_INTERFACE, config->iface);
@ -2517,8 +2511,7 @@ static CURLcode transfer_per_config(struct GlobalConfig *global,
/* Check we have a url */ /* Check we have a url */
if(!config->url_list || !config->url_list->url) { if(!config->url_list || !config->url_list->url) {
helpf(global->errors, "(%d) no URL specified!\n", helpf(stderr, "(%d) no URL specified!\n", CURLE_FAILED_INIT);
CURLE_FAILED_INIT);
return CURLE_FAILED_INIT; return CURLE_FAILED_INIT;
} }
@ -2576,7 +2569,7 @@ static CURLcode transfer_per_config(struct GlobalConfig *global,
if(!config->capath) { if(!config->capath) {
curl_free(env); curl_free(env);
curl_easy_cleanup(curltls); curl_easy_cleanup(curltls);
helpf(global->errors, "out of memory\n"); helpf(stderr, "out of memory\n");
return CURLE_OUT_OF_MEMORY; return CURLE_OUT_OF_MEMORY;
} }
capath_from_env = true; capath_from_env = true;
@ -2694,7 +2687,7 @@ CURLcode operate(struct GlobalConfig *global, int argc, argv_item_t argv[])
/* If we had no arguments then make sure a url was specified in .curlrc */ /* If we had no arguments then make sure a url was specified in .curlrc */
if((argc < 2) && (!global->first->url_list)) { if((argc < 2) && (!global->first->url_list)) {
helpf(global->errors, NULL); helpf(stderr, NULL);
result = CURLE_FAILED_INIT; result = CURLE_FAILED_INIT;
} }
} }

4
src/tool_progress.c
View File

@ -173,7 +173,7 @@ bool progress_meter(struct GlobalConfig *global,
header = TRUE; header = TRUE;
fputs("DL% UL% Dled Uled Xfers Live " fputs("DL% UL% Dled Uled Xfers Live "
"Total Current Left Speed\n", "Total Current Left Speed\n",
global->errors); stderr);
} }
if(final || (diff > 500)) { if(final || (diff > 500)) {
char time_left[10]; char time_left[10];
@ -275,7 +275,7 @@ bool progress_meter(struct GlobalConfig *global,
} }
time2str(time_spent, spent); time2str(time_spent, spent);
fprintf(global->errors, fprintf(stderr,
"\r" "\r"
"%-3s " /* percent downloaded */ "%-3s " /* percent downloaded */
"%-3s " /* percent uploaded */ "%-3s " /* percent uploaded */

9
src/tool_setup.h
View File

@ -37,6 +37,15 @@
#include "curl_setup.h" /* from the lib directory */ #include "curl_setup.h" /* from the lib directory */
extern FILE *tool_stderr;
#if !defined(CURL_DO_NOT_OVERRIDE_STDERR) && !defined(UNITTESTS)
#ifdef stderr
#undef stderr
#endif
#define stderr tool_stderr
#endif
/* /*
* curl tool certainly uses libcurl's external interface. * curl tool certainly uses libcurl's external interface.
*/ */

72
src/tool_stderr.c Normal file
View File

@ -0,0 +1,72 @@
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/* In this file, stdio.h's stderr macro is not overridden. */
#define CURL_DO_NOT_OVERRIDE_STDERR
#include "tool_setup.h"
#include "tool_stderr.h"
#include "memdebug.h" /* keep this as LAST include */
/* In other tool files stderr is defined as tool_stderr by tool_setup.h */
FILE *tool_stderr;
void tool_init_stderr(void)
{
tool_stderr = stderr;
}
void tool_set_stderr_file(char *filename)
{
FILE *fp;
if(!filename)
return;
if(!strcmp(filename, "-")) {
tool_stderr = stdout;
return;
}
/* precheck that filename is accessible to lessen the chance that the
subsequent freopen will fail. */
fp = fopen(filename, FOPEN_WRITETEXT);
if(!fp) {
fprintf(tool_stderr, "Warning: Failed to open %s!\n", filename);
return;
}
fclose(fp);
/* freopen the actual stderr (stdio.h stderr) instead of tool_stderr since
the latter may be set to stdout. */
fp = freopen(filename, FOPEN_WRITETEXT, stderr);
if(!fp) {
/* stderr may have been closed by freopen. there is nothing to be done. */
DEBUGASSERT(0);
return;
}
tool_stderr = stderr;
}

31
src/tool_stderr.h Normal file
View File

@ -0,0 +1,31 @@
#ifndef HEADER_CURL_TOOL_STDERR_H
#define HEADER_CURL_TOOL_STDERR_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "tool_setup.h"
void tool_init_stderr(void);
void tool_set_stderr_file(char *filename);
#endif /* HEADER_CURL_TOOL_STDERR_H */

2
src/tool_writeout.c
View File

@ -427,7 +427,7 @@ void ourWriteOut(struct OperationConfig *config, struct per_transfer *per,
stream = stdout; stream = stdout;
break; break;
case VAR_STDERR: case VAR_STDERR:
stream = config->global->errors; stream = stderr;
break; break;
case VAR_JSON: case VAR_JSON:
ourWriteOutJSON(stream, variables, per, per_result); ourWriteOutJSON(stream, variables, per, per_result);