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/* |
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ROHC Project 2003 at Lulea University of Technology, Sweden. |
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Authors: Andreas Vernersson <andver-8@student.luth.se> |
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Daniel Pettersson <danpet-7@student.luth.se> |
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Erik Soderstrom <soderstrom@yahoo.com> |
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Fredrik Lindstrom <frelin-9@student.luth.se> |
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Johan Stenmark <johste-8@student.luth.se> |
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Martin Juhlin <juhlin@users.sourceforge.net> |
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Mikael Larsson <larmik-9@student.luth.se> |
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Robert Maxe <robmax-1@student.luth.se> |
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|
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Copyright (C) 2003 Andreas Vernersson, Daniel Pettersson, |
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Erik Soderström, Fredrik Lindström, Johan Stenmark, |
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Martin Juhlin, Mikael Larsson, Robert Maxe. |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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#include "comp.h" |
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#include "c_util.h" |
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#include "feedback.h" |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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// Builds a feedback1-package |
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// Param sn: sequence-number |
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// Param f: pointer to feedback packet |
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// Return: true if build was ok |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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bool f_feedback1(int sn, struct sd_feedback * f) |
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{ |
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// int req_sn_bits = calc_feedback_sn_size(); //check if feddback1 is ok .. |
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// if (req_sn_bits < 9) { |
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f->feedback_type = 1; //set type for add_option |
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f->size = 1; |
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f->feedback[0] = (sn & 0xFF); |
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return true; |
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// } |
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// return false; |
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} |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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// Builds a feedback2-package |
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// Param achtype: ACK, NACK or S-NACK |
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// Param mode: mode in which ROHC operates; U-, O- or R-MODE |
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// Param sn: sequence-number |
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// Param f: pointer to feedback packet |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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void f_feedback2(int acktype, int mode, int sn, struct sd_feedback * f) |
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{ |
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// int req_sn_bits=-1; |
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char tkn = (sn & 0xFF); |
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f->size = 2; // size of feedback-2 head |
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|
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f->feedback_type = 2; //set type for add_option |
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|
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f->feedback[0] = (acktype & 0x3) << 6 | (mode & 0x3) << 4; |
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|
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// req_sn_bits = calc_feedback_sn_size(); |
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|
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if(sn < 255){ //12 bits sn |
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// if(req_sn_bits < 13){ |
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f->feedback[0] |= (sn & 0xF00) >> 8; |
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f->feedback[1] = sn & 0xFF; |
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} else { //20 bits sn |
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f->feedback[0] |= (sn & 0xF0000) >> 16; |
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f->feedback[1] = sn & 0xFF00 >> 8; |
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f_add_option(f, OPT_TYPE_SN, &tkn); //return ! important .. |
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} |
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} |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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// Adds an option data for feedback2 |
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// Param f: pointer to feedback packet |
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// Param opt_type: type of option to be added |
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// Param data: the option data |
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// Return: 0 if failed, 1 if ok |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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bool f_add_option(struct sd_feedback * f, int opt_type, char * data) |
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{ |
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if (f->feedback_type == 2) { |
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f->feedback[f->size] = opt_type & 0xF; |
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f->feedback[f->size] <<= 4; |
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f->feedback[f->size] = (data ? 1 : 0) | f->feedback[f->size]; |
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f->size++; |
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|
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if(opt_type == OPT_TYPE_CRC || data) { |
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if(opt_type == OPT_TYPE_CRC) |
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f->feedback[f->size] = 0; |
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else |
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f->feedback[f->size] = data[0]; |
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f->size++; |
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} |
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return true; |
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} |
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return false; |
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} |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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// Appends the cid on the feedback packet |
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// Param f: pointer to the feedback packet |
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// Param cid: the context-id |
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// Param largecidUsed: ==1 if largecid is used |
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// Return: true if cid was successfully appended, else false |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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bool f_append_cid(struct sd_feedback * f, int cid, int largecidUsed) |
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{ |
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char * acid; |
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int largecidsize, i; |
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|
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if(largecidUsed) { // largecid |
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largecidsize = c_bytesSdvl(cid); |
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if(f->size+largecidsize > 30) { |
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rohc_debugf(0, "ERROR [feedback.c - f_append_cid()]: Array to small!\n"); |
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return(false); |
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} else { |
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for(i=f->size-1; i>=0; i--) |
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f->feedback[i+largecidsize] = f->feedback[i]; |
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} |
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acid = (char*)kmalloc(largecidsize, GFP_ATOMIC); |
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if(!acid) { |
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f->size = 0; |
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return(false); |
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} |
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if(!c_encodeSdvl(acid, cid)) { |
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rohc_debugf(0, "ERROR [feedback.c - f_append_cid()]: This should never happen!\n"); |
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return(false); |
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} |
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memcpy(f->feedback, acid, largecidsize); |
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kfree(acid); |
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f->size += largecidsize; |
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} else { |
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if(cid > 0 && cid < 16) { |
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for(i = f->size-1; i>=0; i--) |
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f->feedback[i+1] = f->feedback[i]; |
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f->feedback[0] = 0xE0; |
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f->feedback[0] = (cid & 0xF) | f->feedback[0]; |
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f->size++; |
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} |
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} |
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return(true); |
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} |
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|
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//---------------------------------------------------------------------------------------------------------------------------------- |
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// Wrap the feedback packet and add a CRC-option if specified |
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// Param f: the pointer to the feedback packet |
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// Param cid: the context-id |
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// Param largecidUsed: ==1 if largecid is used, else ==0 |
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// Param with_crc: if ==1, the CRC option will be added to the feedback packet |
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// Param final_size: final size of the feedback packet will be written to this variable |
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// Return: NULL if failed, otherwise the pointer to the feedback packet |
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//---------------------------------------------------------------------------------------------------------------------------------- |
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char * f_wrap_feedback(struct sd_feedback * f, int cid, int largecidUsed, int with_crc, int * final_size) |
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{ |
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unsigned int crc; |
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char * feedback; |
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|
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if (!f_append_cid(f, cid, largecidUsed)) |
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return NULL; |
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if(with_crc) { |
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f_add_option(f, OPT_TYPE_CRC, (char*)1); |
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feedback = (char*)kmalloc(f->size, GFP_ATOMIC); |
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if (!feedback) { |
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f->size = 0; |
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return NULL; |
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} |
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memcpy(feedback, f->feedback, f->size); |
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crc = crc_calculate(CRC_TYPE_8, feedback, f->size); |
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feedback[f->size-1] = (char)(crc & 0xFF); |
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*final_size = f->size; |
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f->size = 0; |
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return(feedback); |
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} |
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|
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feedback = (char*)kmalloc(f->size, GFP_ATOMIC); |
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if (!feedback) { |
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f->size = 0; |
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return NULL; |
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} |
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memcpy(feedback, f->feedback, f->size); |
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*final_size = f->size; |
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f->size = 0; |
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return(feedback); |
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} |
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//---------------------------------------------------------------------------------------------------------------------------------- |