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Code Issues Releases Wiki Activity
31238d5fb7
curl/src/tool_formparse.c
Patrick Monnerat e49e5eaa10 cli tool: fix mime post with --disable-libcurl-option configure option 
Reported-by: Marcel Raad
Fixes #3576
Closes #3583
2019-02-19 17:08:58 +01:00

920 lines
25 KiB
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/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2019, 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.haxx.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.
*
***************************************************************************/
#include "tool_setup.h"
#include "strcase.h"
#define ENABLE_CURLX_PRINTF
/* use our own printf() functions */
#include "curlx.h"
#include "tool_cfgable.h"
#include "tool_convert.h"
#include "tool_msgs.h"
#include "tool_binmode.h"
#include "tool_getparam.h"
#include "tool_paramhlp.h"
#include "tool_formparse.h"
#include "memdebug.h" /* keep this as LAST include */
/* Macros to free const pointers. */
#define CONST_FREE(x) free((void *) (x))
#define CONST_SAFEFREE(x) Curl_safefree(*((void **) &(x)))
/* tool_mime functions. */
static tool_mime *tool_mime_new(tool_mime *parent, toolmimekind kind)
{
tool_mime *m = (tool_mime *) calloc(1, sizeof(*m));
if(m) {
m->kind = kind;
m->parent = parent;
if(parent) {
m->prev = parent->subparts;
parent->subparts = m;
}
}
return m;
}
static tool_mime *tool_mime_new_parts(tool_mime *parent)
{
return tool_mime_new(parent, TOOLMIME_PARTS);
}
static tool_mime *tool_mime_new_data(tool_mime *parent, const char *data)
{
tool_mime *m = NULL;
data = strdup(data);
if(data) {
m = tool_mime_new(parent, TOOLMIME_DATA);
if(!m)
CONST_FREE(data);
else
m->data = data;
}
return m;
}
static tool_mime *tool_mime_new_filedata(tool_mime *parent,
const char *filename,
bool isremotefile,
CURLcode *errcode)
{
CURLcode result = CURLE_OK;
tool_mime *m = NULL;
*errcode = CURLE_OUT_OF_MEMORY;
if(strcmp(filename, "-")) {
/* This is a normal file. */
filename = strdup(filename);
if(filename) {
m = tool_mime_new(parent, TOOLMIME_FILE);
if(!m)
CONST_FREE(filename);
else {
m->data = filename;
if(!isremotefile)
m->kind = TOOLMIME_FILEDATA;
*errcode = CURLE_OK;
}
}
}
else { /* Standard input. */
int fd = fileno(stdin);
char *data = NULL;
curl_off_t size;
curl_off_t origin;
struct_stat sbuf;
set_binmode(stdin);
origin = ftell(stdin);
/* If stdin is a regular file, do not buffer data but read it
when needed. */
if(fd >= 0 && origin >= 0 && !fstat(fd, &sbuf) &&
#ifdef __VMS
sbuf.st_fab_rfm != FAB$C_VAR && sbuf.st_fab_rfm != FAB$C_VFC &&
#endif
S_ISREG(sbuf.st_mode)) {
size = sbuf.st_size - origin;
if(size < 0)
size = 0;
}
else { /* Not suitable for direct use, buffer stdin data. */
size_t stdinsize = 0;
if(file2memory(&data, &stdinsize, stdin) != PARAM_OK) {
/* Out of memory. */
return m;
}
if(ferror(stdin)) {
result = CURLE_READ_ERROR;
Curl_safefree(data);
data = NULL;
}
else if(!stdinsize) {
/* Zero-length data has been freed. Re-create it. */
data = strdup("");
if(!data)
return m;
}
size = curlx_uztoso(stdinsize);
origin = 0;
}
m = tool_mime_new(parent, TOOLMIME_STDIN);
if(!m)
Curl_safefree(data);
else {
m->data = data;
m->origin = origin;
m->size = size;
m->curpos = 0;
if(!isremotefile)
m->kind = TOOLMIME_STDINDATA;
*errcode = result;
}
}
return m;
}
void tool_mime_free(tool_mime *mime)
{
if(mime) {
if(mime->subparts)
tool_mime_free(mime->subparts);
if(mime->prev)
tool_mime_free(mime->prev);
CONST_SAFEFREE(mime->name);
CONST_SAFEFREE(mime->filename);
CONST_SAFEFREE(mime->type);
CONST_SAFEFREE(mime->encoder);
CONST_SAFEFREE(mime->data);
curl_slist_free_all(mime->headers);
free(mime);
}
}
/* Mime part callbacks for stdin. */
size_t tool_mime_stdin_read(char *buffer,
size_t size, size_t nitems, void *arg)
{
tool_mime *sip = (tool_mime *) arg;
curl_off_t bytesleft;
(void) size; /* Always 1: ignored. */
if(sip->size >= 0) {
if(sip->curpos >= sip->size)
return 0; /* At eof. */
bytesleft = sip->size - sip->curpos;
if(curlx_uztoso(nitems) > bytesleft)
nitems = curlx_sotouz(bytesleft);
}
if(nitems) {
if(sip->data) {
/* Return data from memory. */
memcpy(buffer, sip->data + curlx_sotouz(sip->curpos), nitems);
}
else {
/* Read from stdin. */
nitems = fread(buffer, 1, nitems, stdin);
if(ferror(stdin)) {
/* Show error only once. */
if(sip->config) {
warnf(sip->config, "stdin: %s\n", strerror(errno));
sip->config = NULL;
}
return CURL_READFUNC_ABORT;
}
}
sip->curpos += curlx_uztoso(nitems);
}
return nitems;
}
int tool_mime_stdin_seek(void *instream, curl_off_t offset, int whence)
{
tool_mime *sip = (tool_mime *) instream;
switch(whence) {
case SEEK_CUR:
offset += sip->curpos;
break;
case SEEK_END:
offset += sip->size;
break;
}
if(offset < 0)
return CURL_SEEKFUNC_CANTSEEK;
if(!sip->data) {
if(fseek(stdin, (long) (offset + sip->origin), SEEK_SET))
return CURL_SEEKFUNC_CANTSEEK;
}
sip->curpos = offset;
return CURL_SEEKFUNC_OK;
}
/* Translate an internal mime tree into a libcurl mime tree. */
static CURLcode tool2curlparts(CURL *curl, tool_mime *m, curl_mime *mime)
{
CURLcode ret = CURLE_OK;
curl_mimepart *part = NULL;
curl_mime *submime = NULL;
const char *filename = NULL;
if(m) {
ret = tool2curlparts(curl, m->prev, mime);
if(!ret) {
part = curl_mime_addpart(mime);
if(!part)
ret = CURLE_OUT_OF_MEMORY;
}
if(!ret) {
filename = m->filename;
switch(m->kind) {
case TOOLMIME_PARTS:
ret = tool2curlmime(curl, m, &submime);
if(!ret) {
ret = curl_mime_subparts(part, submime);
if(ret)
curl_mime_free(submime);
}
break;
case TOOLMIME_DATA:
#ifdef CURL_DOES_CONVERSIONS
/* Our data is always textual: convert it to ASCII. */
{
size_t size = strlen(m->data);
char *cp = malloc(size + 1);
if(!cp)
ret = CURLE_OUT_OF_MEMORY;
else {
memcpy(cp, m->data, size + 1);
ret = convert_to_network(cp, size);
if(!ret)
ret = curl_mime_data(part, cp, CURL_ZERO_TERMINATED);
free(cp);
}
}
#else
ret = curl_mime_data(part, m->data, CURL_ZERO_TERMINATED);
#endif
break;
case TOOLMIME_FILE:
case TOOLMIME_FILEDATA:
ret = curl_mime_filedata(part, m->data);
if(!ret && m->kind == TOOLMIME_FILEDATA && !filename)
ret = curl_mime_filename(part, NULL);
break;
case TOOLMIME_STDIN:
if(!filename)
filename = "-";
/* FALLTHROUGH */
case TOOLMIME_STDINDATA:
ret = curl_mime_data_cb(part, m->size,
(curl_read_callback) tool_mime_stdin_read,
(curl_seek_callback) tool_mime_stdin_seek,
NULL, m);
break;
default:
/* Other cases not possible in this context. */
break;
}
}
if(!ret && filename)
ret = curl_mime_filename(part, filename);
if(!ret)
ret = curl_mime_type(part, m->type);
if(!ret)
ret = curl_mime_headers(part, m->headers, 0);
if(!ret)
ret = curl_mime_encoder(part, m->encoder);
if(!ret)
ret = curl_mime_name(part, m->name);
}
return ret;
}
CURLcode tool2curlmime(CURL *curl, tool_mime *m, curl_mime **mime)
{
CURLcode ret = CURLE_OK;
*mime = curl_mime_init(curl);
if(!*mime)
ret = CURLE_OUT_OF_MEMORY;
else
ret = tool2curlparts(curl, m->subparts, *mime);
if(ret) {
curl_mime_free(*mime);
*mime = NULL;
}
return ret;
}
/*
* helper function to get a word from form param
* after call get_parm_word, str either point to string end
* or point to any of end chars.
*/
static char *get_param_word(char **str, char **end_pos, char endchar)
{
char *ptr = *str;
char *word_begin = NULL;
char *ptr2;
char *escape = NULL;
/* the first non-space char is here */
word_begin = ptr;
if(*ptr == '"') {
++ptr;
while(*ptr) {
if(*ptr == '\\') {
if(ptr[1] == '\\' || ptr[1] == '"') {
/* remember the first escape position */
if(!escape)
escape = ptr;
/* skip escape of back-slash or double-quote */
ptr += 2;
continue;
}
}
if(*ptr == '"') {
*end_pos = ptr;
if(escape) {
/* has escape, we restore the unescaped string here */
ptr = ptr2 = escape;
do {
if(*ptr == '\\' && (ptr[1] == '\\' || ptr[1] == '"'))
++ptr;
*ptr2++ = *ptr++;
}
while(ptr < *end_pos);
*end_pos = ptr2;
}
while(*ptr && *ptr != ';' && *ptr != endchar)
++ptr;
*str = ptr;
return word_begin + 1;
}
++ptr;
}
/* end quote is missing, treat it as non-quoted. */
ptr = word_begin;
}
while(*ptr && *ptr != ';' && *ptr != endchar)
++ptr;
*str = *end_pos = ptr;
return word_begin;
}
/* Append slist item and return -1 if failed. */
static int slist_append(struct curl_slist **plist, const char *data)
{
struct curl_slist *s = curl_slist_append(*plist, data);
if(!s)
return -1;
*plist = s;
return 0;
}
/* Read headers from a file and append to list. */
static int read_field_headers(struct OperationConfig *config,
const char *filename, FILE *fp,
struct curl_slist **pheaders)
{
size_t hdrlen = 0;
size_t pos = 0;
bool incomment = FALSE;
int lineno = 1;
char hdrbuf[999]; /* Max. header length + 1. */
for(;;) {
int c = getc(fp);
if(c == EOF || (!pos && !ISSPACE(c))) {
/* Strip and flush the current header. */
while(hdrlen && ISSPACE(hdrbuf[hdrlen - 1]))
hdrlen--;
if(hdrlen) {
hdrbuf[hdrlen] = '\0';
if(slist_append(pheaders, hdrbuf)) {
fprintf(config->global->errors,
"Out of memory for field headers!\n");
return -1;
}
hdrlen = 0;
}
}
switch(c) {
case EOF:
if(ferror(fp)) {
fprintf(config->global->errors,
"Header file %s read error: %s\n", filename, strerror(errno));
return -1;
}
return 0; /* Done. */
case '\r':
continue; /* Ignore. */
case '\n':
pos = 0;
incomment = FALSE;
lineno++;
continue;
case '#':
if(!pos)
incomment = TRUE;
break;
}
pos++;
if(!incomment) {
if(hdrlen == sizeof(hdrbuf) - 1) {
warnf(config->global, "File %s line %d: header too long (truncated)\n",
filename, lineno);
c = ' ';
}
if(hdrlen <= sizeof(hdrbuf) - 1)
hdrbuf[hdrlen++] = (char) c;
}
}
/* NOTREACHED */
}
static int get_param_part(struct OperationConfig *config, char endchar,
char **str, char **pdata, char **ptype,
char **pfilename, char **pencoder,
struct curl_slist **pheaders)
{
char *p = *str;
char *type = NULL;
char *filename = NULL;
char *encoder = NULL;
char *endpos;
char *tp;
char sep;
char type_major[128] = "";
char type_minor[128] = "";
char *endct = NULL;
struct curl_slist *headers = NULL;
if(ptype)
*ptype = NULL;
if(pfilename)
*pfilename = NULL;
if(pheaders)
*pheaders = NULL;
if(pencoder)
*pencoder = NULL;
while(ISSPACE(*p))
p++;
tp = p;
*pdata = get_param_word(&p, &endpos, endchar);
/* If not quoted, strip trailing spaces. */
if(*pdata == tp)
while(endpos > *pdata && ISSPACE(endpos[-1]))
endpos--;
sep = *p;
*endpos = '\0';
while(sep == ';') {
while(ISSPACE(*++p))
;
if(!endct && checkprefix("type=", p)) {
for(p += 5; ISSPACE(*p); p++)
;
/* set type pointer */
type = p;
/* verify that this is a fine type specifier */
if(2 != sscanf(type, "%127[^/ ]/%127[^;, \n]", type_major, type_minor)) {
warnf(config->global, "Illegally formatted content-type field!\n");
curl_slist_free_all(headers);
return -1; /* illegal content-type syntax! */
}
/* now point beyond the content-type specifier */
p = type + strlen(type_major) + strlen(type_minor) + 1;
for(endct = p; *p && *p != ';' && *p != endchar; p++)
if(!ISSPACE(*p))
endct = p + 1;
sep = *p;
}
else if(checkprefix("filename=", p)) {
if(endct) {
*endct = '\0';
endct = NULL;
}
for(p += 9; ISSPACE(*p); p++)
;
tp = p;
filename = get_param_word(&p, &endpos, endchar);
/* If not quoted, strip trailing spaces. */
if(filename == tp)
while(endpos > filename && ISSPACE(endpos[-1]))
endpos--;
sep = *p;
*endpos = '\0';
}
else if(checkprefix("headers=", p)) {
if(endct) {
*endct = '\0';
endct = NULL;
}
p += 8;
if(*p == '@' || *p == '<') {
char *hdrfile;
FILE *fp;
/* Read headers from a file. */
do {
p++;
} while(ISSPACE(*p));
tp = p;
hdrfile = get_param_word(&p, &endpos, endchar);
/* If not quoted, strip trailing spaces. */
if(hdrfile == tp)
while(endpos > hdrfile && ISSPACE(endpos[-1]))
endpos--;
sep = *p;
*endpos = '\0';
/* TODO: maybe special fopen for VMS? */
fp = fopen(hdrfile, FOPEN_READTEXT);
if(!fp)
warnf(config->global, "Cannot read from %s: %s\n", hdrfile,
strerror(errno));
else {
int i = read_field_headers(config, hdrfile, fp, &headers);
fclose(fp);
if(i) {
curl_slist_free_all(headers);
return -1;
}
}
}
else {
char *hdr;
while(ISSPACE(*p))
p++;
tp = p;
hdr = get_param_word(&p, &endpos, endchar);
/* If not quoted, strip trailing spaces. */
if(hdr == tp)
while(endpos > hdr && ISSPACE(endpos[-1]))
endpos--;
sep = *p;
*endpos = '\0';
if(slist_append(&headers, hdr)) {
fprintf(config->global->errors, "Out of memory for field header!\n");
curl_slist_free_all(headers);
return -1;
}
}
}
else if(checkprefix("encoder=", p)) {
if(endct) {
*endct = '\0';
endct = NULL;
}
for(p += 8; ISSPACE(*p); p++)
;
tp = p;
encoder = get_param_word(&p, &endpos, endchar);
/* If not quoted, strip trailing spaces. */
if(encoder == tp)
while(endpos > encoder && ISSPACE(endpos[-1]))
endpos--;
sep = *p;
*endpos = '\0';
}
else if(endct) {
/* This is part of content type. */
for(endct = p; *p && *p != ';' && *p != endchar; p++)
if(!ISSPACE(*p))
endct = p + 1;
sep = *p;
}
else {
/* unknown prefix, skip to next block */
char *unknown = get_param_word(&p, &endpos, endchar);
sep = *p;
*endpos = '\0';
if(*unknown)
warnf(config->global, "skip unknown form field: %s\n", unknown);
}
}
/* Terminate content type. */
if(endct)
*endct = '\0';
if(ptype)
*ptype = type;
else if(type)
warnf(config->global, "Field content type not allowed here: %s\n", type);
if(pfilename)
*pfilename = filename;
else if(filename)
warnf(config->global,
"Field file name not allowed here: %s\n", filename);
if(pencoder)
*pencoder = encoder;
else if(encoder)
warnf(config->global,
"Field encoder not allowed here: %s\n", encoder);
if(pheaders)
*pheaders = headers;
else if(headers) {
warnf(config->global,
"Field headers not allowed here: %s\n", headers->data);
curl_slist_free_all(headers);
}
*str = p;
return sep & 0xFF;
}
/***************************************************************************
*
* formparse()
*
* Reads a 'name=value' parameter and builds the appropriate linked list.
*
* If the value is of the form '<filename', field data is read from the
* given file.
* Specify files to upload with 'name=@filename', or 'name=@"filename"'
* in case the filename contain ',' or ';'. Supports specified
* given Content-Type of the files. Such as ';type=<content-type>'.
*
* If literal_value is set, any initial '@' or '<' in the value string
* loses its special meaning, as does any embedded ';type='.
*
* You may specify more than one file for a single name (field). Specify
* multiple files by writing it like:
*
* 'name=@filename,filename2,filename3'
*
* or use double-quotes quote the filename:
*
* 'name=@"filename","filename2","filename3"'
*
* If you want content-types specified for each too, write them like:
*
* 'name=@filename;type=image/gif,filename2,filename3'
*
* If you want custom headers added for a single part, write them in a separate
* file and do like this:
*
* 'name=foo;headers=@headerfile' or why not
* 'name=@filemame;headers=@headerfile'
*
* To upload a file, but to fake the file name that will be included in the
* formpost, do like this:
*
* 'name=@filename;filename=/dev/null' or quote the faked filename like:
* 'name=@filename;filename="play, play, and play.txt"'
*
* If filename/path contains ',' or ';', it must be quoted by double-quotes,
* else curl will fail to figure out the correct filename. if the filename
* tobe quoted contains '"' or '\', '"' and '\' must be escaped by backslash.
*
***************************************************************************/
/* Convenience macros for null pointer check. */
#define NULL_CHECK(ptr, init, retcode) { \
(ptr) = (init); \
if(!(ptr)) { \
warnf(config->global, "out of memory!\n"); \
curl_slist_free_all(headers); \
Curl_safefree(contents); \
return retcode; \
} \
}
#define SET_TOOL_MIME_PTR(m, field, retcode) { \
if(field) \
NULL_CHECK((m)->field, strdup(field), retcode); \
}
int formparse(struct OperationConfig *config,
const char *input,
tool_mime **mimeroot,
tool_mime **mimecurrent,
bool literal_value)
{
/* input MUST be a string in the format 'name=contents' and we'll
build a linked list with the info */
char *name = NULL;
char *contents = NULL;
char *contp;
char *data;
char *type = NULL;
char *filename = NULL;
char *encoder = NULL;
struct curl_slist *headers = NULL;
tool_mime *part = NULL;
CURLcode res;
/* Allocate the main mime structure if needed. */
if(!*mimecurrent) {
NULL_CHECK(*mimeroot, tool_mime_new_parts(NULL), 1);
*mimecurrent = *mimeroot;
}
/* Make a copy we can overwrite. */
NULL_CHECK(contents, strdup(input), 2);
/* Scan for the end of the name. */
contp = strchr(contents, '=');
if(contp) {
int sep = '\0';
if(contp > contents)
name = contents;
*contp++ = '\0';
if(*contp == '(' && !literal_value) {
/* Starting a multipart. */
sep = get_param_part(config, '\0',
&contp, &data, &type, NULL, NULL, &headers);
if(sep < 0) {
Curl_safefree(contents);
return 3;
}
NULL_CHECK(part, tool_mime_new_parts(*mimecurrent), 4);
*mimecurrent = part;
part->headers = headers;
headers = NULL;
SET_TOOL_MIME_PTR(part, type, 5);
}
else if(!name && !strcmp(contp, ")") && !literal_value) {
/* Ending a multipart. */
if(*mimecurrent == *mimeroot) {
warnf(config->global, "no multipart to terminate!\n");
Curl_safefree(contents);
return 6;
}
*mimecurrent = (*mimecurrent)->parent;
}
else if('@' == contp[0] && !literal_value) {
/* we use the @-letter to indicate file name(s) */
tool_mime *subparts = NULL;
do {
/* since this was a file, it may have a content-type specifier
at the end too, or a filename. Or both. */
++contp;
sep = get_param_part(config, ',', &contp,
&data, &type, &filename, &encoder, &headers);
if(sep < 0) {
Curl_safefree(contents);
return 7;
}
/* now contp point to comma or string end.
If more files to come, make sure we have multiparts. */
if(!subparts) {
if(sep != ',') /* If there is a single file. */
subparts = *mimecurrent;
else
NULL_CHECK(subparts, tool_mime_new_parts(*mimecurrent), 8);
}
/* Store that file in a part. */
NULL_CHECK(part,
tool_mime_new_filedata(subparts, data, TRUE, &res), 9);
part->headers = headers;
headers = NULL;
part->config = config->global;
if(res == CURLE_READ_ERROR) {
/* An error occurred while reading stdin: if read has started,
issue the error now. Else, delay it until processed by
libcurl. */
if(part->size > 0) {
warnf(config->global,
"error while reading standard input\n");
Curl_safefree(contents);
return 10;
}
CONST_SAFEFREE(part->data);
part->data = NULL;
part->size = -1;
res = CURLE_OK;
}
SET_TOOL_MIME_PTR(part, filename, 11);
SET_TOOL_MIME_PTR(part, type, 12);
SET_TOOL_MIME_PTR(part, encoder, 13);
/* *contp could be '\0', so we just check with the delimiter */
} while(sep); /* loop if there's another file name */
part = (*mimecurrent)->subparts; /* Set name on group. */
}
else {
if(*contp == '<' && !literal_value) {
++contp;
sep = get_param_part(config, '\0', &contp,
&data, &type, NULL, &encoder, &headers);
if(sep < 0) {
Curl_safefree(contents);
return 14;
}
NULL_CHECK(part, tool_mime_new_filedata(*mimecurrent, data, FALSE,
&res), 15);
part->headers = headers;
headers = NULL;
part->config = config->global;
if(res == CURLE_READ_ERROR) {
/* An error occurred while reading stdin: if read has started,
issue the error now. Else, delay it until processed by
libcurl. */
if(part->size > 0) {
warnf(config->global,
"error while reading standard input\n");
Curl_safefree(contents);
return 16;
}
CONST_SAFEFREE(part->data);
part->data = NULL;
part->size = -1;
res = CURLE_OK;
}
}
else {
if(literal_value)
data = contp;
else {
sep = get_param_part(config, '\0', &contp,
&data, &type, &filename, &encoder, &headers);
if(sep < 0) {
Curl_safefree(contents);
return 17;
}
}
NULL_CHECK(part, tool_mime_new_data(*mimecurrent, data), 18);
part->headers = headers;
headers = NULL;
}
SET_TOOL_MIME_PTR(part, filename, 19);
SET_TOOL_MIME_PTR(part, type, 20);
SET_TOOL_MIME_PTR(part, encoder, 21);
if(sep) {
*contp = (char) sep;
warnf(config->global,
"garbage at end of field specification: %s\n", contp);
}
}
/* Set part name. */
SET_TOOL_MIME_PTR(part, name, 22);
}
else {
warnf(config->global, "Illegally formatted input field!\n");
Curl_safefree(contents);
return 23;
}
Curl_safefree(contents);
return 0;
}
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