attr_override.c

[詳解]

/*++
/* NAME
/*  attr_override 3
/* SUMMARY
/*  apply name=value settings from string
/* SYNOPSIS
/*  #include <attr_override.h>
/*
/*  void    attr_override(bp, delimiters, parens, ... CA_ATTR_OVER_END);
/*  char    *bp;
/*  const char *delimiters;
/*  const char *parens;
/* DESCRIPTION
/*  This routine updates the values of known in-memory variables
/*  based on the name=value specifications from an input string.
/*  The input format supports parentheses around name=value to
/*  allow whitespace around "=" and within values.
/*
/*  This may be used, for example, with client endpoint
/*  specifications or with policy tables to allow selective
/*  overrides of global main.cf parameter settings (timeouts,
/*  fall-back policies, etc.).
/*
/*  Arguments:
/* .IP bp
/*  Pointer to input string. The input is modified.
/* .IP "delimiters, parens"
/*  See mystrtok(3) for description. Typical values are
/*  CHARS_COMMA_SP and CHARS_BRACE, respectively.
/* .PP
/*  The parens argument is followed by a list of macros
/*  with arguments. Each macro may appear only once.  The list
/*  must be terminated with CA_ATTR_OVER_END which has no argument.
/*  The following describes the expected values.
/* .IP "CA_ATTR_OVER_STR_TABLE(const ATTR_OVER_STR *)"
/*  The macro argument specifies a null-terminated table with
/*  attribute names, assignment targets, and range limits which
/*  should be the same as for the corresponding main.cf parameters.
/* .IP "CA_ATTR_OVER_TIME_TABLE(const ATTR_OVER_TIME *)"
/*  The macro argument specifies a null-terminated table with
/*  attribute names, their default time units (leading digits
/*  are skipped), assignment targets, and range limits which
/*  should be the same as for the corresponding main.cf parameters.
/* .IP "CA_ATTR_OVER_INT_TABLE(const ATTR_OVER_INT *)"
/*  The macro argument specifies a null-terminated table with
/*  attribute names, assignment targets, and range limits which
/*  should be the same as for the corresponding main.cf parameters.
/* SEE ALSO
/*  mystrtok(3), safe tokenizer
/*  extpar(3), extract text from parentheses
/*  split_nameval(3), name-value splitter
/* DIAGNOSTICS
/*  Panic: interface violations.
/*
/*  Fatal errors: memory allocation problem, syntax error,
/*  out-of-range error.
/* LICENSE
/* .ad
/* .fi
/*  The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*  Wietse Venema
/*  IBM T.J. Watson Research
/*  P.O. Box 704
/*  Yorktown Heights, NY 10598, USA
/*--*/

 /*
  * System library.
  */
#include <sys_defs.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>         /* strtol() */

 /*
  * Utility library.
  */
#include <msg.h>
#include <stringops.h>

 /*
  * Global library.
  */
#include <mail_conf.h>
#include <conv_time.h>
#include <attr_override.h>

/* attr_override - apply settings from list of attribute=value pairs */

void    attr_override(char *cp, const char *sep, const char *parens,...)
{
    static const char myname[] = "attr_override";
    va_list ap;
    int     idx;
    char   *nameval;
    const ATTR_OVER_INT *int_table = 0;
    const ATTR_OVER_STR *str_table = 0;
    const ATTR_OVER_TIME *time_table = 0;

    /*
     * Get the lookup tables and assignment targets.
     */
    va_start(ap, parens);
    while ((idx = va_arg(ap, int)) != ATTR_OVER_END) {
    switch (idx) {
    case ATTR_OVER_INT_TABLE:
        if (int_table)
        msg_panic("%s: multiple ATTR_OVER_INT_TABLE", myname);
        int_table = va_arg(ap, const ATTR_OVER_INT *);
        break;
    case ATTR_OVER_STR_TABLE:
        if (str_table)
        msg_panic("%s: multiple ATTR_OVER_STR_TABLE", myname);
        str_table = va_arg(ap, const ATTR_OVER_STR *);
        break;
    case ATTR_OVER_TIME_TABLE:
        if (time_table)
        msg_panic("%s: multiple ATTR_OVER_TIME_TABLE", myname);
        time_table = va_arg(ap, const ATTR_OVER_TIME *);
        break;
    default:
        msg_panic("%s: unknown argument type: %d", myname, idx);
    }
    }
    va_end(ap);

    /*
     * Process each attribute=value override in the input string.
     */
    while ((nameval = mystrtokq(&cp, sep, parens)) != 0) {
    int     found = 0;
    char   *key;
    char   *value;
    const char *err;
    const ATTR_OVER_INT *ip;
    const ATTR_OVER_STR *sp;
    const ATTR_OVER_TIME *tp;
    int     int_val;
    int     def_unit;
    char   *end;
    long    longval;

    /*
     * Split into name and value.
     */
    /* { name = value } */
    if (*nameval == parens[0]
        && (err = extpar(&nameval, parens, EXTPAR_FLAG_NONE)) != 0)
        msg_fatal("%s in \"%s\"", err, nameval);
    if ((err = split_nameval(nameval, &key, &value)) != 0)
        msg_fatal("malformed option: %s: \"...%s...\"", err, nameval);

    /*
     * Look up the name and apply the value.
     */
    for (sp = str_table; sp != 0 && found == 0 && sp->name != 0; sp++) {
        if (strcmp(sp->name, key) != 0)
        continue;
        check_mail_conf_str(sp->name, value, sp->min, sp->max);
        sp->target[0] = value;
        found = 1;
    }
    for (ip = int_table; ip != 0 && found == 0 && ip->name != 0; ip++) {
        if (strcmp(ip->name, key) != 0)
        continue;
        /* XXX Duplicated from mail_conf_int(3). */
        errno = 0;
        int_val = longval = strtol(value, &end, 10);
        if (*value == 0 || *end != 0 || errno == ERANGE
        || longval != int_val)
        msg_fatal("bad numerical configuration: %s = %s", key, value);
        check_mail_conf_int(key, int_val, ip->min, ip->max);
        ip->target[0] = int_val;
        found = 1;
    }
    for (tp = time_table; tp != 0 && found == 0 && tp->name != 0; tp++) {
        if (strcmp(tp->name, key) != 0)
        continue;
        def_unit = tp->defval[strspn(tp->defval, "0123456789")];
        if (conv_time(value, &int_val, def_unit) == 0)
        msg_fatal("%s: bad time value or unit: %s", key, value);
        check_mail_conf_time(key, int_val, tp->min, tp->max);
        tp->target[0] = int_val;
        found = 1;
    }
    if (found == 0)
        msg_fatal("unknown option: \"%s = %s\"", key, value);
    }
}