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Full Discussion: Segmentation fault when debugging in C
Top Forums Programming Segmentation fault when debugging in C Post 302705439 by Don Cragun on Monday 24th of September 2012 11:33:51 PM
Old 09-25-2012
So, you're getting another error. If you want help, you need to tell us what the error is and give us a way to track it down. This is your program we're trying to debug. Most of us don't have access to your system (or any system running contiki os) and don't have (or want) tinyECC packages on our systems. The comments I've given you are just based on reading your code, knowing what generates a segmentation fault, and a few decades of experience writing C programs.

As to your last comment. If I understand correctly, you now have the following four lines of code in your source:
Code:
int xxx = 2*KEYDIGITS*NN_DIGIT_LEN + 1 + 20+ 20;
uint8_t *C = malloc(xxx*sizeof(uint8_t));
int C_len = 2*KEYDIGITS*NN_DIGIT_LEN + 1 + 20 + 20;
int oct_len = ecc_point2octet(C, C_len, &pbkey_alice, 0);

Wouldn't it make more sense to replace this with:
Code:
int C_len = 2*KEYDIGITS*NN_DIGIT_LEN + 1 + 20 + 20;
uint8_t *C = malloc(C_len*sizeof(uint8_t));
int oct_len = ecc_point2octet(C, C_len, &pbkey_alice, 0);

(since xxx is a duplicate of C_len) or, if C_len isn't used anywhere else, with:
Code:
uint8_t *C = malloc((2*KEYDIGITS*NN_DIGIT_LEN+1+20+20)*sizeof(uint8_t));
int oct_len = ecc_point2octet(C, sizeof(C), &pbkey_alice, 0);

This User Gave Thanks to Don Cragun For This Post:
chap
 

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LEARN ABOUT CENTOS

xcb_xkb_controls_notify_event_t

xcb_xkb_controls_notify_event_t(3)				    XCB Events					xcb_xkb_controls_notify_event_t(3)

NAME

       xcb_xkb_controls_notify_event_t -

SYNOPSIS

       #include <xcb/xkb.h>

   Event datastructure
       typedef struct xcb_xkb_controls_notify_event_t {
	   uint8_t	   response_type;
	   uint8_t	   xkbType;
	   uint16_t	   sequence;
	   xcb_timestamp_t time;
	   uint8_t	   deviceID;
	   uint8_t	   numGroups;
	   uint8_t	   pad0[2];
	   uint32_t	   changedControls;
	   uint32_t	   enabledControls;
	   uint32_t	   enabledControlChanges;
	   xcb_keycode_t   keycode;
	   uint8_t	   eventType;
	   uint8_t	   requestMajor;
	   uint8_t	   requestMinor;
	   uint8_t	   pad1[4];
       } xcb_xkb_controls_notify_event_t;

EVENT FIELDS

       response_type
		 The type of this event, in this case XCB_XKB_CONTROLS_NOTIFY. This field is also present in the xcb_generic_event_t and can be
		 used to tell events apart from each other.

       sequence  The sequence number of the last request processed by the X11 server.

       xkbType	 NOT YET DOCUMENTED.

       time	 NOT YET DOCUMENTED.

       deviceID  NOT YET DOCUMENTED.

       numGroups NOT YET DOCUMENTED.

       changedControls
		 NOT YET DOCUMENTED.

       enabledControls
		 NOT YET DOCUMENTED.

       enabledControlChanges
		 NOT YET DOCUMENTED.

       keycode	 NOT YET DOCUMENTED.

       eventType NOT YET DOCUMENTED.

       requestMajor
		 NOT YET DOCUMENTED.

       requestMinor
		 NOT YET DOCUMENTED.

DESCRIPTION

SEE ALSO

AUTHOR

       Generated from xkb.xml. Contact xcb@lists.freedesktop.org for corrections and improvements.

XCB
								    2014-06-10					xcb_xkb_controls_notify_event_t(3)
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