safec  2.1
Safe C Library - ISO TR24731 Bounds Checking Interface
strljustify_s.c
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1 /*------------------------------------------------------------------
2  * strljustify_s.c
3  *
4  * November 2008, Bo Berry
5  *
6  * Copyright (c) 2008-2011 by Cisco Systems, Inc
7  * All rights reseved.
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 
70 errno_t
71 strljustify_s (char *dest, rsize_t dmax)
72 {
73  char *orig_dest;
74  rsize_t orig_dmax;
75 
76  if (dest == NULL) {
77  invoke_safe_str_constraint_handler("strljustify_s_s: "
78  "dest is null",
79  NULL, ESNULLP);
80  return (ESNULLP);
81  }
82 
83  if (dmax == 0 ) {
84  invoke_safe_str_constraint_handler("strljustify_s_s: "
85  "dmax is 0",
86  NULL, ESZEROL);
87  return (ESZEROL);
88  }
89 
90  if (dmax > RSIZE_MAX_STR) {
91  invoke_safe_str_constraint_handler("strljustify_s_s: "
92  "dmax exceeds max",
93  NULL, ESLEMAX);
94  return (ESLEMAX);
95  }
96 
97  /*
98  * corner cases, a dmax of one allows only for a null
99  */
100  if (dmax <= RSIZE_MIN_STR) {
101  *dest = '\0';
102  return (EOK);
103  }
104  if (*dest == '\0') {
105  return (EOK);
106  }
107 
108  orig_dmax = dmax;
109  orig_dest = dest;
110 
111  /*
112  * scan the string to be sure it is properly terminated
113  */
114  while (*dest) {
115  if (dmax == 0) {
116  while (orig_dmax) { *orig_dest++ = '\0'; orig_dmax--; }
117 
119  "strljustify_s: dest is unterminated",
120  NULL, ESUNTERM);
121  return (ESUNTERM);
122  }
123  dmax--;
124  dest++;
125  }
126 
127  /*
128  * find first non-white space char
129  */
130  dest = orig_dest;
131  while ((*dest == ' ') || (*dest == '\t')) {
132  dest++;
133  }
134 
135  /*
136  * shift text, removing spaces, to left justify
137  */
138  if (orig_dest != dest) {
139  while (*dest) {
140  *orig_dest++ = *dest;
141  *dest++ = ' ';
142  }
143  *orig_dest = '\0';
144  }
145 
146  return (EOK);
147 }
void invoke_safe_str_constraint_handler(const char *msg, void *ptr, errno_t error)
Invokes the currently set constraint handler or the default.
errno_t strljustify_s(char *dest, rsize_t dmax)
Removes beginning whitespace from the string pointed to by dest by shifting the text left over writti...
Definition: strljustify_s.c:71