projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 0f5e4452 KS |
1 | /* Copyright (c) 1979 Regents of the University of California */ |
| 2 | # | |
| 3 | ||
| 4 | #include "rcv.h" | |
| 5 | ||
| 6 | /* | |
| 7 | * Mail -- a mail program | |
| 8 | * | |
| 9 | * Variable handling stuff. | |
| 10 | */ | |
| 11 | ||
| 12 | /* | |
| 13 | * Assign a value to a variable. | |
| 14 | */ | |
| 15 | ||
| 16 | assign(name, value) | |
| 17 | char name[], value[]; | |
| 18 | { | |
| 19 | register struct var *vp; | |
| 20 | register int h; | |
| 21 | ||
| 22 | h = hash(name); | |
| 23 | vp = lookup(name); | |
| 24 | if (vp == NOVAR) { | |
| 25 | vp = (struct var *) calloc(sizeof *vp, 1); | |
| 26 | vp->v_name = vcopy(name); | |
| 27 | vp->v_link = variables[h]; | |
| 28 | variables[h] = vp; | |
| 29 | } | |
| 30 | else | |
| 31 | vfree(vp->v_value); | |
| 32 | vp->v_value = vcopy(value); | |
| 33 | } | |
| 34 | ||
| 35 | /* | |
| 36 | * Free up a variable string. We do not bother to allocate | |
| 37 | * strings whose value is "" since they are expected to be frequent. | |
| 38 | * Thus, we cannot free same! | |
| 39 | */ | |
| 40 | ||
| 41 | vfree(cp) | |
| 42 | register char *cp; | |
| 43 | { | |
| 44 | if (!equal(cp, "")) | |
| 45 | cfree(cp); | |
| 46 | } | |
| 47 | ||
| 48 | /* | |
| 49 | * Copy a variable value into permanent (ie, not collected after each | |
| 50 | * command) space. Do not bother to alloc space for "" | |
| 51 | */ | |
| 52 | ||
| 53 | char * | |
| 54 | vcopy(str) | |
| 55 | char str[]; | |
| 56 | { | |
| 57 | register char *top, *cp, *cp2; | |
| 58 | ||
| 59 | if (equal(str, "")) | |
| 60 | return(""); | |
| 61 | top = calloc(strlen(str)+1, 1); | |
| 62 | cp = top; | |
| 63 | cp2 = str; | |
| 64 | while (*cp++ = *cp2++) | |
| 65 | ; | |
| 66 | return(top); | |
| 67 | } | |
| 68 | ||
| 69 | /* | |
| 70 | * Get the value of a variable and return it. | |
| 71 | * Look in the environment if its not available locally. | |
| 72 | */ | |
| 73 | ||
| 74 | char * | |
| 75 | value(name) | |
| 76 | char name[]; | |
| 77 | { | |
| 78 | register struct var *vp; | |
| 79 | ||
| 80 | if ((vp = lookup(name)) == NOVAR) | |
| 81 | return(getenv(name)); | |
| 82 | return(vp->v_value); | |
| 83 | } | |
| 84 | ||
| 85 | /* | |
| 86 | * Locate a variable and return its variable | |
| 87 | * node. | |
| 88 | */ | |
| 89 | ||
| 90 | struct var * | |
| 91 | lookup(name) | |
| 92 | char name[]; | |
| 93 | { | |
| 94 | register struct var *vp; | |
| 95 | register int h; | |
| 96 | ||
| 97 | h = hash(name); | |
| 98 | for (vp = variables[h]; vp != NOVAR; vp = vp->v_link) | |
| 99 | if (equal(vp->v_name, name)) | |
| 100 | return(vp); | |
| 101 | return(NOVAR); | |
| 102 | } | |
| 103 | ||
| 104 | /* | |
| 105 | * Locate a group name and return it. | |
| 106 | */ | |
| 107 | ||
| 108 | struct grouphead * | |
| 109 | findgroup(name) | |
| 110 | char name[]; | |
| 111 | { | |
| 112 | register struct grouphead *gh; | |
| 113 | register int h; | |
| 114 | ||
| 115 | h = hash(name); | |
| 116 | for (gh = groups[h]; gh != NOGRP; gh = gh->g_link) | |
| 117 | if (equal(gh->g_name, name)) | |
| 118 | return(gh); | |
| 119 | return(NOGRP); | |
| 120 | } | |
| 121 | ||
| 122 | /* | |
| 123 | * Print a group out on stdout | |
| 124 | */ | |
| 125 | ||
| 126 | printgroup(name) | |
| 127 | char name[]; | |
| 128 | { | |
| 129 | register struct grouphead *gh; | |
| 130 | register struct group *gp; | |
| 131 | ||
| 132 | if ((gh = findgroup(name)) == NOGRP) { | |
| 133 | printf("\"%s\": not a group\n", name); | |
| 134 | return; | |
| 135 | } | |
| 136 | printf("%s\t", gh->g_name); | |
| 137 | for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link) | |
| 138 | printf(" %s", gp->ge_name); | |
| 139 | printf("\n"); | |
| 140 | } | |
| 141 | ||
| 142 | /* | |
| 143 | * Hash the passed string and return an index into | |
| 144 | * the variable or group hash table. | |
| 145 | */ | |
| 146 | ||
| 147 | hash(name) | |
| 148 | char name[]; | |
| 149 | { | |
| 150 | register int h; | |
| 151 | register char *cp; | |
| 152 | ||
| 153 | for (cp = name, h = 0; *cp; h = (h << 2) + *cp++) | |
| 154 | ; | |
| 155 | h &= ~0100000; | |
| 156 | return(h % HSHSIZE); | |
| 157 | } |