usr.sbin/cron/lib/env.c

   1 /* Copyright 1988,1990,1993,1994 by Paul Vixie
   2  * All rights reserved
   3  *
   4  * Distribute freely, except: don't remove my name from the source or
   5  * documentation (don't take credit for my work), mark your changes (don't
   6  * get me blamed for your possible bugs), don't alter or remove this
   7  * notice.  May be sold if buildable source is provided to buyer.  No
   8  * warrantee of any kind, express or implied, is included with this
   9  * software; use at your own risk, responsibility for damages (if any) to
  10  * anyone resulting from the use of this software rests entirely with the
  11  * user.
  12  *
  13  * Send bug reports, bug fixes, enhancements, requests, flames, etc., and
  14  * I'll try to keep a version up to date.  I can be reached as follows:
  15  * Paul Vixie          <paul@vix.com>          uunet!decwrl!vixie!paul
  16  *
  17  * $FreeBSD: src/usr.sbin/cron/lib/env.c,v 1.7.2.1 2000/07/01 10:35:07 ps Exp $
  18  * $DragonFly: src/usr.sbin/cron/lib/env.c,v 1.5 2004/12/18 22:48:03 swildner Exp $
  19  */
  20
  21 #include "cron.h"
  22
  23
  24 char **
  25 env_init(void)
  26 {
  27         char **p;
  28
  29         p = malloc(sizeof(char *));
  30         if (p)
  31                 p[0] = NULL;
  32         return (p);
  33 }
  34
  35
  36 void
  37 env_free(char **envp)
  38 {
  39         char    **p;
  40
  41         for (p = envp;  *p;  p++)
  42                 free(*p);
  43         free(envp);
  44 }
  45
  46
  47 char **
  48 env_copy(char **envp)
  49 {
  50         int count, i;
  51         char **p;
  52
  53         for (count = 0;  envp[count] != NULL;  count++)
  54                 ;
  55         p = (char **) malloc((count+1) * sizeof(char *)); /* 1 for the NULL */
  56         if (p == NULL) {
  57                 errno = ENOMEM;
  58                 return NULL;
  59         }
  60         for (i = 0;  i < count;  i++)
  61                 if ((p[i] = strdup(envp[i])) == NULL) {
  62                         while (--i >= 0)
  63                                 free(p[i]);
  64                         free(p);
  65                         errno = ENOMEM;
  66                         return NULL;
  67                 }
  68         p[count] = NULL;
  69         return (p);
  70 }
  71
  72
  73 char **
  74 env_set(char **envp, char *envstr)
  75 {
  76         int count, found;
  77         char **p;
  78         char *q;
  79
  80         /*
  81          * count the number of elements, including the null pointer;
  82          * also set 'found' to -1 or index of entry if already in here.
  83          */
  84         found = -1;
  85         for (count = 0;  envp[count] != NULL;  count++) {
  86                 if (!strcmp_until(envp[count], envstr, '='))
  87                         found = count;
  88         }
  89         count++;        /* for the NULL */
  90
  91         if (found != -1) {
  92                 /*
  93                  * it exists already, so just free the existing setting,
  94                  * save our new one there, and return the existing array.
  95                  */
  96                 q = envp[found];
  97                 if ((envp[found] = strdup(envstr)) == NULL) {
  98                         envp[found] = q;
  99                         /* XXX env_free(envp); */
 100                         errno = ENOMEM;
 101                         return NULL;
 102                 }
 103                 free(q);
 104                 return (envp);
 105         }
 106
 107         /*
 108          * it doesn't exist yet, so resize the array, move null pointer over
 109          * one, save our string over the old null pointer, and return resized
 110          * array.
 111          */
 112         p = (char **) realloc((void *) envp,
 113                               (unsigned) ((count+1) * sizeof(char *)));
 114         if (p == NULL)  {
 115                 /* XXX env_free(envp); */
 116                 errno = ENOMEM;
 117                 return NULL;
 118         }
 119         p[count] = p[count-1];
 120         if ((p[count-1] = strdup(envstr)) == NULL) {
 121                 env_free(p);
 122                 errno = ENOMEM;
 123                 return NULL;
 124         }
 125         return (p);
 126 }
 127
 128
 129 /* return       ERR = end of file
 130  *              FALSE = not an env setting (file was repositioned)
 131  *              TRUE = was an env setting
 132  */
 133 int
 134 load_env(char *envstr, FILE *f)
 135 {
 136         long    filepos;
 137         int     fileline;
 138         char    name[MAX_ENVSTR], val[MAX_ENVSTR];
 139         int     fields;
 140
 141         filepos = ftell(f);
 142         fileline = LineNumber;
 143         skip_comments(f);
 144         if (EOF == get_string(envstr, MAX_ENVSTR, f, "\n"))
 145                 return (ERR);
 146
 147         Debug(DPARS, ("load_env, read <%s>\n", envstr))
 148
 149         name[0] = val[0] = '\0';
 150         fields = sscanf(envstr, "%[^ =] = %[^\n#]", name, val);
 151         if (fields != 2) {
 152                 Debug(DPARS, ("load_env, not 2 fields (%d)\n", fields))
 153                 fseek(f, filepos, 0);
 154                 Set_LineNum(fileline);
 155                 return (FALSE);
 156         }
 157
 158         /* 2 fields from scanf; looks like an env setting
 159          */
 160
 161         /*
 162          * process value string
 163          */
 164         /*local*/{
 165                 int     len = strdtb(val);
 166
 167                 if (len >= 2) {
 168                         if (val[0] == '\'' || val[0] == '"') {
 169                                 if (val[len-1] == val[0]) {
 170                                         val[len-1] = '\0';
 171                                         strcpy(val, val+1);
 172                                 }
 173                         }
 174                 }
 175         }
 176
 177         if (strlen(name) + 1 + strlen(val) >= MAX_ENVSTR-1)
 178                 return (FALSE);
 179         sprintf(envstr, "%s=%s", name, val);
 180         Debug(DPARS, ("load_env, <%s> <%s> -> <%s>\n", name, val, envstr))
 181         return (TRUE);
 182 }
 183
 184
 185 char *
 186 env_get(char *name, char **envp)
 187 {
 188         int len;
 189         char *p, *q;
 190
 191         len = strlen(name);
 192         while ((p = *envp++)) {
 193                 if (!(q = strchr(p, '=')))
 194                         continue;
 195                 if ((q - p) == len && !strncmp(p, name, len))
 196                         return (q+1);
 197         }
 198         return (NULL);
 199 }