curl/lib/mime.h
Patrick Monnerat eb559c8056
mime: relax easy/mime structures binding
Deprecation and removal of codeset conversion support from the library
have released the strict need for an early binding of mime structures to
an easy handle (https://github.com/curl/curl/commit/2610142).

This constraint currently forces to create the handle before the mime
structure and the latter cannot be attached to another handle once
created (see https://curl.se/mail/lib-2022-08/0027.html).

This commit removes the handle pointers from the mime structures
allowing more flexibility on their use.

When an easy handle is duplicated, bound mime structures must however
still be duplicated too as their components hold send-time dynamic
information.

Closes #9927
2022-11-28 09:09:54 +01:00

175 lines
7.2 KiB
C

#ifndef HEADER_CURL_MIME_H
#define HEADER_CURL_MIME_H
/***************************************************************************
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*
* Copyright (C) 1998 - 2022, 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
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***************************************************************************/
#include "curl_setup.h"
#define MIME_BOUNDARY_DASHES 24 /* leading boundary dashes */
#define MIME_RAND_BOUNDARY_CHARS 16 /* Nb. of random boundary chars. */
#define MAX_ENCODED_LINE_LENGTH 76 /* Maximum encoded line length. */
#define ENCODING_BUFFER_SIZE 256 /* Encoding temp buffers size. */
/* Part flags. */
#define MIME_USERHEADERS_OWNER (1 << 0)
#define MIME_BODY_ONLY (1 << 1)
#define MIME_FAST_READ (1 << 2)
#define FILE_CONTENTTYPE_DEFAULT "application/octet-stream"
#define MULTIPART_CONTENTTYPE_DEFAULT "multipart/mixed"
#define DISPOSITION_DEFAULT "attachment"
/* Part source kinds. */
enum mimekind {
MIMEKIND_NONE = 0, /* Part not set. */
MIMEKIND_DATA, /* Allocated mime data. */
MIMEKIND_FILE, /* Data from file. */
MIMEKIND_CALLBACK, /* Data from `read' callback. */
MIMEKIND_MULTIPART, /* Data is a mime subpart. */
MIMEKIND_LAST
};
/* Readback state tokens. */
enum mimestate {
MIMESTATE_BEGIN, /* Readback has not yet started. */
MIMESTATE_CURLHEADERS, /* In curl-generated headers. */
MIMESTATE_USERHEADERS, /* In caller's supplied headers. */
MIMESTATE_EOH, /* End of headers. */
MIMESTATE_BODY, /* Placeholder. */
MIMESTATE_BOUNDARY1, /* In boundary prefix. */
MIMESTATE_BOUNDARY2, /* In boundary. */
MIMESTATE_CONTENT, /* In content. */
MIMESTATE_END, /* End of part reached. */
MIMESTATE_LAST
};
/* Mime headers strategies. */
enum mimestrategy {
MIMESTRATEGY_MAIL, /* Mime mail. */
MIMESTRATEGY_FORM, /* HTTP post form. */
MIMESTRATEGY_LAST
};
/* Content transfer encoder. */
struct mime_encoder {
const char * name; /* Encoding name. */
size_t (*encodefunc)(char *buffer, size_t size, bool ateof,
curl_mimepart *part); /* Encoded read. */
curl_off_t (*sizefunc)(curl_mimepart *part); /* Encoded size. */
};
/* Content transfer encoder state. */
struct mime_encoder_state {
size_t pos; /* Position on output line. */
size_t bufbeg; /* Next data index in input buffer. */
size_t bufend; /* First unused byte index in input buffer. */
char buf[ENCODING_BUFFER_SIZE]; /* Input buffer. */
};
/* Mime readback state. */
struct mime_state {
enum mimestate state; /* Current state token. */
void *ptr; /* State-dependent pointer. */
curl_off_t offset; /* State-dependent offset. */
};
/* Boundary string length. */
#define MIME_BOUNDARY_LEN (MIME_BOUNDARY_DASHES + MIME_RAND_BOUNDARY_CHARS)
/* A mime multipart. */
struct curl_mime {
curl_mimepart *parent; /* Parent part. */
curl_mimepart *firstpart; /* First part. */
curl_mimepart *lastpart; /* Last part. */
char boundary[MIME_BOUNDARY_LEN + 1]; /* The part boundary. */
struct mime_state state; /* Current readback state. */
};
/* A mime part. */
struct curl_mimepart {
curl_mime *parent; /* Parent mime structure. */
curl_mimepart *nextpart; /* Forward linked list. */
enum mimekind kind; /* The part kind. */
unsigned int flags; /* Flags. */
char *data; /* Memory data or file name. */
curl_read_callback readfunc; /* Read function. */
curl_seek_callback seekfunc; /* Seek function. */
curl_free_callback freefunc; /* Argument free function. */
void *arg; /* Argument to callback functions. */
FILE *fp; /* File pointer. */
struct curl_slist *curlheaders; /* Part headers. */
struct curl_slist *userheaders; /* Part headers. */
char *mimetype; /* Part mime type. */
char *filename; /* Remote file name. */
char *name; /* Data name. */
curl_off_t datasize; /* Expected data size. */
struct mime_state state; /* Current readback state. */
const struct mime_encoder *encoder; /* Content data encoder. */
struct mime_encoder_state encstate; /* Data encoder state. */
size_t lastreadstatus; /* Last read callback returned status. */
};
CURLcode Curl_mime_add_header(struct curl_slist **slp, const char *fmt, ...);
#if !defined(CURL_DISABLE_MIME) && (!defined(CURL_DISABLE_HTTP) || \
!defined(CURL_DISABLE_SMTP) || \
!defined(CURL_DISABLE_IMAP))
/* Prototypes. */
void Curl_mime_initpart(struct curl_mimepart *part);
void Curl_mime_cleanpart(struct curl_mimepart *part);
CURLcode Curl_mime_duppart(struct Curl_easy *data,
struct curl_mimepart *dst,
const curl_mimepart *src);
CURLcode Curl_mime_set_subparts(struct curl_mimepart *part,
struct curl_mime *subparts,
int take_ownership);
CURLcode Curl_mime_prepare_headers(struct Curl_easy *data,
struct curl_mimepart *part,
const char *contenttype,
const char *disposition,
enum mimestrategy strategy);
curl_off_t Curl_mime_size(struct curl_mimepart *part);
size_t Curl_mime_read(char *buffer, size_t size, size_t nitems,
void *instream);
CURLcode Curl_mime_rewind(struct curl_mimepart *part);
const char *Curl_mime_contenttype(const char *filename);
void Curl_mime_unpause(struct curl_mimepart *part);
#else
/* if disabled */
#define Curl_mime_initpart(x)
#define Curl_mime_cleanpart(x)
#define Curl_mime_duppart(x,y,z) CURLE_OK /* Nothing to duplicate. Succeed */
#define Curl_mime_set_subparts(a,b,c) CURLE_NOT_BUILT_IN
#define Curl_mime_prepare_headers(a,b,c,d,e) CURLE_NOT_BUILT_IN
#define Curl_mime_size(x) (curl_off_t) -1
#define Curl_mime_read NULL
#define Curl_mime_rewind(x) ((void)x, CURLE_NOT_BUILT_IN)
#define Curl_mime_unpause(x)
#endif
#endif /* HEADER_CURL_MIME_H */