/*++ /* NAME /* postconf_lookup 3 /* SUMMARY /* parameter lookup routines /* SYNOPSIS /* #include <postconf.h> /* /* const char *pcf_lookup_parameter_value(mode, name, local_scope, node) /* int mode; /* const char *name; /* PCF_MASTER_ENT *local_scope; /* PCF_PARAM_NODE *node; /* /* char *pcf_expand_parameter_value(buf, mode, value, local_scope) /* VSTRING *buf; /* int mode; /* const char *value; /* PCF_MASTER_ENT *local_scope; /* DESCRIPTION /* These functions perform parameter value lookups. The order /* of decreasing precedence is: /* .IP \(bu /* Search name=value parameter settings in master.cf. These /* lookups are disabled with the PCF_SHOW_DEFS flag. /* .IP \(bu /* Search name=value parameter settings in main.cf. These /* lookups are disabled with the PCF_SHOW_DEFS flag. /* .IP \(bu /* Search built-in default parameter settings. These lookups /* are disabled with the PCF_SHOW_NONDEF flag. /* .PP /* pcf_lookup_parameter_value() looks up the value for the /* named parameter, and returns null if the name was not found. /* /* pcf_expand_parameter_value() expands $name in the specified /* parameter value. This function ignores the PCF_SHOW_NONDEF /* flag. The result value is a pointer to storage in a /* user-supplied buffer, or in a buffer that is overwritten /* with each call. /* /* Arguments: /* .IP buf /* Null buffer pointer, or pointer to user-supplied buffer. /* .IP mode /* Bit-wise OR of zero or one of the following (other flags /* are ignored): /* .RS /* .IP PCF_SHOW_DEFS /* Search built-in default parameter settings only. /* .IP PCF_SHOW_NONDEF /* Search local (master.cf) and global (main.cf) name=value /* parameter settings only. /* .RE /* .IP name /* The name of a parameter to be looked up. /* .IP value /* The parameter value where $name should be expanded. /* .IP local_scope /* Pointer to master.cf entry with local name=value settings, /* or a null pointer (i.e. no local parameter lookup). /* .IP node /* Global default value for the named parameter, or a null /* pointer (i.e. do the global default lookup anyway). /* DIAGNOSTICS /* Problems are reported to the standard error stream. /* 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 <string.h> /* Utility library. */ #include <msg.h> #include <mymalloc.h> #include <vstring.h> #include <dict.h> #include <stringops.h> #include <mac_expand.h> /* Global library. */ #include <mail_conf.h> /* Application-specific. */ #include <postconf.h> #define STR(x) vstring_str(x) /* pcf_lookup_parameter_value - look up specific parameter value */ const char *pcf_lookup_parameter_value(int mode, const char *name, PCF_MASTER_ENT *local_scope, PCF_PARAM_NODE *node) { const char *value = 0; /* * Local name=value entries in master.cf take precedence over global * name=value entries in main.cf. Built-in defaults have the lowest * precedence. */ if ((mode & PCF_SHOW_DEFS) != 0 || ((local_scope == 0 || local_scope->all_params == 0 || (value = dict_get(local_scope->all_params, name)) == 0) && (value = dict_lookup(CONFIG_DICT, name)) == 0 && (mode & PCF_SHOW_NONDEF) == 0)) { if (node != 0 || (node = PCF_PARAM_TABLE_FIND(pcf_param_table, name)) != 0) value = pcf_convert_param_node(PCF_SHOW_DEFS, name, node); } return (value); } /* * Data structure to pass private state while recursively expanding $name in * parameter values. */ typedef struct { int mode; PCF_MASTER_ENT *local_scope; } PCF_EVAL_CTX; /* pcf_lookup_parameter_value_wrapper - macro parser call-back routine */ static const char *pcf_lookup_parameter_value_wrapper(const char *key, int unused_type, void *context) { PCF_EVAL_CTX *cp = (PCF_EVAL_CTX *) context; return (pcf_lookup_parameter_value(cp->mode, key, cp->local_scope, (PCF_PARAM_NODE *) 0)); } /* pcf_expand_parameter_value - expand $name in parameter value */ char *pcf_expand_parameter_value(VSTRING *buf, int mode, const char *value, PCF_MASTER_ENT *local_scope) { const char *myname = "pcf_expand_parameter_value"; static VSTRING *local_buf; int status; PCF_EVAL_CTX eval_ctx; /* * Initialize. */ if (buf == 0) { if (local_buf == 0) local_buf = vstring_alloc(10); buf = local_buf; } /* * Expand macros recursively. * * When expanding $name in "postconf -n" parameter values, don't limit the * search to only non-default parameter values. * * When expanding $name in "postconf -d" parameter values, do limit the * search to only default parameter values. */ #define DONT_FILTER (char *) 0 eval_ctx.mode = (mode & ~PCF_SHOW_NONDEF); eval_ctx.local_scope = local_scope; status = mac_expand(buf, value, MAC_EXP_FLAG_RECURSE, DONT_FILTER, pcf_lookup_parameter_value_wrapper, (void *) &eval_ctx); if (status & MAC_PARSE_ERROR) msg_fatal("macro processing error"); if (msg_verbose > 1) { if (strcmp(value, STR(buf)) != 0) msg_info("%s: expand %s -> %s", myname, value, STR(buf)); else msg_info("%s: const %s", myname, value); } return (STR(buf)); }