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Member "motion-Release-4.3.0/src/netcam_wget.c" (14 Jan 2020, 10130 Bytes) of package /linux/misc/motion-Release-4.3.0.tar.gz:


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    1 /*
    2 Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2002
    3     Free Software Foundation, Inc.
    4 
    5 Additional Copyright (C) 2004-2005 Christopher Price,
    6 Angel Carpintero, and other contributing authors.
    7 
    8 Major part of this file is reused code from GNU Wget. It has been
    9 merged and modified for use in the program Motion which is also
   10 released under the terms of the GNU General Public License.
   11 
   12 GNU Wget and Motion is free software; you can redistribute it and/or
   13 modify it under the terms of the GNU General Public License as published
   14 by the Free Software Foundation; either version 2 of the License, or
   15 (at your option) any later version.
   16 
   17 GNU Wget is distributed in the hope that it will be useful,
   18 but WITHOUT ANY WARRANTY; without even the implied warranty of
   19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   20 GNU General Public License for more details.
   21 
   22 You should have received a copy of the GNU General Public License
   23 along with Wget; if not, write to the Free Software
   24 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
   25 
   26 #include "motion.h"
   27 #include <ctype.h>
   28 #include <sys/types.h>
   29 #include <sys/socket.h>
   30 
   31 #define MINVAL(x, y) ((x) < (y) ? (x) : (y))
   32 
   33 /* This file contains the generic routines for work with headers.
   34    Currently they are used only by HTTP in http.c, but they can be
   35    used by anything that cares about RFC822-style headers.
   36 
   37    Header is defined in RFC2068, as quoted below.  Note that this
   38    definition is not HTTP-specific -- it is virtually
   39    indistinguishable from the one given in RFC822 or RFC1036.
   40 
   41     message-header = field-name ":" [ field-value ] CRLF
   42 
   43     field-name     = token
   44     field-value    = *( field-content | LWS )
   45 
   46     field-content  = <the OCTETs making up the field-value
   47              and consisting of either *TEXT or combinations
   48              of token, tspecials, and quoted-string>
   49 
   50    The public functions are header_get() and header_process(), which
   51    see.  */
   52 
   53 
   54 /* Get a header from read-buffer RBUF and return it in *HDR.
   55 
   56    As defined in RFC2068 and elsewhere, a header can be folded into
   57    multiple lines if the continuation line begins with a space or
   58    horizontal TAB.  Also, this function will accept a header ending
   59    with just LF instead of CRLF.
   60 
   61    The header may be of arbitrary length; the function will allocate
   62    as much memory as necessary for it to fit.  It need not contain a
   63    `:', thus you can use it to retrieve, say, HTTP status line.
   64 
   65    All trailing whitespace is stripped from the header, and it is
   66    zero-terminated.
   67  */
   68 int header_get(netcam_context_ptr netcam, char **hdr, enum header_get_flags flags)
   69 {
   70     int i;
   71     int bufsize = 80;
   72 
   73     *hdr = mymalloc(bufsize);
   74 
   75     for (i = 0; 1; i++) {
   76         int res;
   77         /* #### Use DO_REALLOC?  */
   78         if (i > bufsize - 1)
   79             *hdr = (char *)myrealloc(*hdr, (bufsize <<= 1), "");
   80 
   81         res = RBUF_READCHAR (netcam, *hdr + i);
   82 
   83         if (res == 1) {
   84             if ((*hdr)[i] == '\n') {
   85                 if (!((flags & HG_NO_CONTINUATIONS) || i == 0
   86                     || (i == 1 && (*hdr)[0] == '\r'))) {
   87                     char next;
   88                     /*
   89                      * If the header is non-empty, we need to check if
   90                      * it continues on to the other line.  We do that by
   91                      * peeking at the next character.
   92                      */
   93                     res = rbuf_peek(netcam, &next);
   94 
   95                     if (res == 0) {
   96                         (*hdr)[i] = '\0';
   97                         return HG_EOF;
   98                     } else if (res == -1) {
   99                         (*hdr)[i] = '\0';
  100                         return HG_ERROR;
  101                     }
  102                     /* If the next character is HT or SP, just continue. */
  103                     if (next == '\t' || next == ' ')
  104                         continue;
  105                 }
  106 
  107                 /*
  108                  * Strip trailing whitespace.  (*hdr)[i] is the newline;
  109                  * decrement I until it points to the last available
  110                  * whitespace.
  111                  */
  112                 while (i > 0 && isspace((*hdr)[i - 1]))
  113                     --i;
  114 
  115                 (*hdr)[i] = '\0';
  116                 break;
  117             }
  118         } else if (res == 0) {
  119             (*hdr)[i] = '\0';
  120             return HG_EOF;
  121         } else {
  122             (*hdr)[i] = '\0';
  123             return HG_ERROR;
  124         }
  125     }
  126 
  127     return HG_OK;
  128 }
  129 
  130 /**
  131  * header_process
  132  *
  133  *  Check whether HEADER begins with NAME and, if yes, skip the `:' and
  134  *  the whitespace, and call PROCFUN with the arguments of HEADER's
  135  *  contents (after the `:' and space) and ARG.  Otherwise, return 0.
  136  */
  137 int header_process(const char *header, const char *name,
  138                     int (*procfun)(const char *, void *), void *arg)
  139 {
  140     /* Check whether HEADER matches NAME. */
  141     while (*name && (tolower (*name) == tolower (*header)))
  142         ++name, ++header;
  143 
  144     if (*name || *header++ != ':')
  145         return 0;
  146 
  147     header += skip_lws (header);
  148     return ((*procfun) (header, arg));
  149 }
  150 
  151 /* Helper functions for use with header_process(). */
  152 
  153 /**
  154  * header_extract_number
  155  *
  156  *  Extract a long integer from HEADER and store it to CLOSURE.  If an
  157  *  error is encountered, return 0, else 1.
  158  */
  159 int header_extract_number(const char *header, void *closure)
  160 {
  161     const char *p = header;
  162     long result;
  163 
  164     for (result = 0; isdigit (*p); p++)
  165         result = 10 * result + (*p - '0');
  166 
  167     /* Failure if no number present. */
  168     if (p == header)
  169         return 0;
  170 
  171     /* Skip trailing whitespace. */
  172     p += skip_lws (p);
  173 
  174     /* We return the value, even if a format error follows. */
  175     *(long *)closure = result;
  176 
  177     /* Indicate failure if trailing garbage is present. */
  178     if (*p)
  179         return 0;
  180 
  181     return 1;
  182 }
  183 
  184 /**
  185  * header_strdup
  186  *
  187  *  Strdup HEADER, and place the pointer to CLOSURE.
  188  */
  189 int header_strdup(const char *header, void *closure)
  190 {
  191     *(char **)closure = mystrdup(header);
  192     return 1;
  193 }
  194 
  195 
  196 /**
  197  * skip_lws
  198  *  Skip LWS (linear white space), if present.  Returns number of
  199  *  characters to skip.
  200  */
  201 int skip_lws(const char *string)
  202 {
  203     const char *p = string;
  204 
  205     while (*p == ' ' || *p == '\t' || *p == '\r' || *p == '\n')
  206         ++p;
  207 
  208     return p - string;
  209 }
  210 
  211 
  212 /**
  213  * motion_base64_encode
  214  *
  215  *   Encode the string S of length LENGTH to base64 format and place it
  216  *   to STORE.  STORE will be 0-terminated, and must point to a writable
  217  *   buffer of at least 1+BASE64_LENGTH(length) bytes.
  218  */
  219 void motion_base64_encode(const char *s, char *store, int length)
  220 {
  221     /* Conversion table.  */
  222     static const char tbl[64] = {
  223     'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
  224     'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
  225     'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
  226     'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
  227     'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
  228     'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
  229     'w', 'x', 'y', 'z', '0', '1', '2', '3',
  230     '4', '5', '6', '7', '8', '9', '+', '/'
  231     };
  232 
  233     int i;
  234     unsigned char *p = (unsigned char *)store;
  235 
  236     /* Transform the 3x8 bits to 4x6 bits, as required by base64. */
  237     for (i = 0; i < length; i += 3) {
  238         *p++ = tbl[s[0] >> 2];
  239         *p++ = tbl[((s[0] & 3) << 4) + (s[1] >> 4)];
  240         *p++ = tbl[((s[1] & 0xf) << 2) + (s[2] >> 6)];
  241         *p++ = tbl[s[2] & 0x3f];
  242         s += 3;
  243     }
  244 
  245     /* Pad the result if necessary... */
  246     if (i == length + 1)
  247         *(p - 1) = '=';
  248     else if (i == length + 2)
  249         *(p - 1) = *(p - 2) = '=';
  250 
  251     /* ...and zero-terminate it.  */
  252     *p = '\0';
  253 }
  254 
  255 /**
  256  * strdupdelim
  257  */
  258 char *strdupdelim(const char *beg, const char *end)
  259 {
  260     char *res = mymalloc(end - beg + 1);
  261     memcpy (res, beg, end - beg);
  262 
  263     res[end - beg] = '\0';
  264     return res;
  265 }
  266 
  267 /**
  268  * http_process_type
  269  */
  270 int http_process_type(const char *hdr, void *arg)
  271 {
  272     char **result = (char **)arg;
  273     /* Locate P on `;' or the terminating zero, whichever comes first. */
  274     const char *p = strchr (hdr, ';');
  275 
  276     if (!p)
  277         p = hdr + strlen (hdr);
  278 
  279     while (p > hdr && isspace (*(p - 1)))
  280         --p;
  281 
  282     *result = strdupdelim (hdr, p);
  283     return 1;
  284 }
  285 
  286 /**
  287  * rbuf_initialize
  288  *
  289  *  This is a simple implementation of buffering IO-read functions.
  290  */
  291 void rbuf_initialize(netcam_context_ptr netcam)
  292 {
  293     netcam->response->buffer_pos = netcam->response->buffer;
  294     netcam->response->buffer_left = 0;
  295 }
  296 
  297 int rbuf_read_bufferful(netcam_context_ptr netcam)
  298 {
  299     return netcam_recv(netcam, netcam->response->buffer,
  300                        sizeof (netcam->response->buffer));
  301 }
  302 
  303 /**
  304  * rbuf_peek
  305  *
  306  *  Like rbuf_readchar(), only don't move the buffer position.
  307  */
  308 int rbuf_peek(netcam_context_ptr netcam, char *store)
  309 {
  310     if (!netcam->response->buffer_left) {
  311         int res;
  312         rbuf_initialize(netcam);
  313         res = netcam_recv (netcam, netcam->response->buffer,
  314                            sizeof (netcam->response->buffer));
  315 
  316         if (res <= 0) {
  317             *store = '\0';
  318             return res;
  319         }
  320 
  321         netcam->response->buffer_left = res;
  322     }
  323 
  324     *store = *netcam->response->buffer_pos;
  325     return 1;
  326 }
  327 
  328 /**
  329  * rbuf_flush
  330  *
  331  *   Flush RBUF's buffer to WHERE.  Flush MAXSIZE bytes at most.
  332  *   Returns the number of bytes actually copied.  If the buffer is
  333  *   empty, 0 is returned.
  334  */
  335 int rbuf_flush(netcam_context_ptr netcam, char *where, int maxsize)
  336 {
  337     if (!netcam->response->buffer_left) {
  338         return 0;
  339     } else {
  340         int howmuch = MINVAL ((int)netcam->response->buffer_left, maxsize);
  341 
  342         if (where)
  343             memcpy(where, netcam->response->buffer_pos, howmuch);
  344 
  345         netcam->response->buffer_left -= howmuch;
  346         netcam->response->buffer_pos += howmuch;
  347         return howmuch;
  348     }
  349 }
  350 
  351 /**
  352  * http_result_code
  353  *
  354  *  Get the HTTP result code
  355  */
  356 int http_result_code(const char *header)
  357 {
  358     char *cptr;
  359 
  360     /* Assure the header starts out right. */
  361     if (strncmp(header, "HTTP", 4))
  362         return -1;
  363 
  364     /* Find the space following the HTTP/1.x */
  365     if ((cptr = strchr(header+4, ' ')) == NULL)
  366         return -1;
  367 
  368     return atoi(cptr + 1);
  369 }
  370