safec  2.1
Safe C Library - ISO TR24731 Bounds Checking Interface
strremovews_s.c
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1 /*------------------------------------------------------------------
2  * strremovews_s.c
3  *
4  * November 2008, Bo Berry
5  *
6  * Copyright (c) 2008-2011 by Cisco Systems, Inc
7  * All rights resevered.
8  *
9  * Permission is hereby granted, free of charge, to any person
10  * obtaining a copy of this software and associated documentation
11  * files (the "Software"), to deal in the Software without
12  * restriction, including without limitation the rights to use,
13  * copy, modify, merge, publish, distribute, sublicense, and/or
14  * sell copies of the Software, and to permit persons to whom the
15  * Software is furnished to do so, subject to the following
16  * conditions:
17  *
18  * The above copyright notice and this permission notice shall be
19  * included in all copies or substantial portions of the Software.
20  *
21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
23  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
25  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
26  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  *------------------------------------------------------------------
30  */
31 
32 #include "safeclib_private.h"
33 #include "safe_str_constraint.h"
34 #include "safe_str_lib.h"
35 
36 
69 errno_t
70 strremovews_s (char *dest, rsize_t dmax)
71 {
72  char *orig_dest;
73  char *orig_end;
74  rsize_t orig_dmax;
75 
76  if (dest == NULL) {
77  invoke_safe_str_constraint_handler("strremovews_s: dest is null",
78  NULL, ESNULLP);
79  return (ESNULLP);
80  }
81 
82  if (dmax == 0 ) {
83  invoke_safe_str_constraint_handler("strremovews_s: dmax is 0",
84  NULL, ESZEROL);
85  return (ESZEROL);
86  }
87 
88  if (dmax > RSIZE_MAX_STR) {
89  invoke_safe_str_constraint_handler("strremovews_s: dmax exceeds max",
90  NULL, ESLEMAX);
91  return (ESLEMAX);
92  }
93 
94  /*
95  * corner case, a dmax of one requires a null
96  */
97  if (*dest == '\0' || dmax <= RSIZE_MIN_STR) {
98  *dest = '\0';
99  return (EOK);
100  }
101 
102  orig_dest = dest;
103  orig_dmax = dmax;
104 
105  /*
106  * scan the string to be sure it is properly terminated
107  */
108  while (*dest) {
109  if (dmax == 0) {
110  while (orig_dmax) { *orig_dest++ = '\0'; orig_dmax--; }
111 
113  "strremovews_s: dest is unterminated",
114  NULL, ESUNTERM);
115  return (ESUNTERM);
116  }
117  dmax--;
118  dest++;
119  }
120 
121  /*
122  * find first non-white space char
123  */
124  orig_end = dest-1;
125  dest = orig_dest;
126  while ((*dest == ' ') || (*dest == '\t')) {
127  dest++;
128  }
129 
130  /*
131  * shift the text over the leading spaces
132  */
133  if (orig_dest != dest && *dest) {
134  while (*dest) {
135  *orig_dest++ = *dest;
136  *dest++ = ' ';
137  }
138  *dest = '\0';
139  }
140 
141  /*
142  * strip trailing whitespace
143  */
144  dest = orig_end;
145  while ((*dest == ' ') || (*dest == '\t')) {
146  *dest = '\0';
147  dest--;
148  }
149 
150  return (EOK);
151 }
errno_t strremovews_s(char *dest, rsize_t dmax)
Removes beginning and trailing whitespace from the string pointed to by dest by shifting the text lef...
Definition: strremovews_s.c:70
void invoke_safe_str_constraint_handler(const char *msg, void *ptr, errno_t error)
Invokes the currently set constraint handler or the default.