/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
#include "libbb.h"
#if ENABLE_FEATURE_SYSLOG
# include <syslog.h>
#endif

#if ENABLE_FEATURE_SYSLOG
static smallint syslog_level = LOG_ERR;
#endif
smallint logmode = LOGMODE_STDIO;
const char *msg_eol = "\n";

void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
{
        char *msg, *msg1;
        char stack_msg[80];
        int applet_len, strerr_len, msgeol_len, used;

        if (!logmode)
                return;

        applet_len = strlen(applet_name) + 2; /* "applet: " */
        strerr_len = strerr ? strlen(strerr) : 0;
        msgeol_len = strlen(msg_eol);

        /* This costs ~90 bytes of code, but avoids costly
         * malloc()[in vasprintf]+realloc()+memmove()+free() in 99% of cases.
         * ~40% speedup.
         */
        if ((int)sizeof(stack_msg) - applet_len > 0) {
                va_list p2;

                /* It is not portable to use va_list twice, need to va_copy it */
                va_copy(p2, p);
                used = vsnprintf(stack_msg + applet_len, (int)sizeof(stack_msg) - applet_len, s, p2);
                va_end(p2);
                msg = stack_msg;
                used += applet_len;
                if (used < (int)sizeof(stack_msg) - 3 - msgeol_len - strerr_len)
                        goto add_pfx_and_sfx;
        }

        used = vasprintf(&msg, s, p);
        if (used < 0)
                return;

        /* This is ugly and costs +60 bytes compared to multiple
         * fprintf's, but is guaranteed to do a single write.
         * This is needed for e.g. httpd logging, when multiple
         * children can produce log messages simultaneously. */

        /* can't use xrealloc: it calls error_msg on failure,
         * that may result in a recursion */
        /* +3 is for ": " before strerr and for terminating NUL */
        msg1 = realloc(msg, applet_len + used + strerr_len + msgeol_len + 3);
        if (!msg1) {
                msg[used++] = '\n'; /* overwrites NUL */
                applet_len = 0;
        } else {
                msg = msg1;
                /* TODO: maybe use writev instead of memmoving? Need full_writev? */
                memmove(msg + applet_len, msg, used);
                used += applet_len;
 add_pfx_and_sfx:
                strcpy(msg, applet_name);
                msg[applet_len - 2] = ':';
                msg[applet_len - 1] = ' ';
                if (strerr) {
                        if (s[0]) { /* not perror_nomsg? */
                                msg[used++] = ':';
                                msg[used++] = ' ';
                        }
                        strcpy(&msg[used], strerr);
                        used += strerr_len;
                }
                strcpy(&msg[used], msg_eol);
                used += msgeol_len;
        }

        if (logmode & LOGMODE_STDIO) {
                fflush_all();
                full_write(STDERR_FILENO, msg, used);
        }
#if ENABLE_FEATURE_SYSLOG
        if (logmode & LOGMODE_SYSLOG) {
                syslog(syslog_level, "%s", msg + applet_len);
        }
#endif
        if (msg != stack_msg)
                free(msg);
}

#ifdef VERSION_WITH_WRITEV
/* Code size is approximately the same, but currently it's the only user
 * of writev in entire bbox. __libc_writev in uclibc is ~50 bytes. */
void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
{
        int strerr_len, msgeol_len;
        struct iovec iov[3];

#define used   (iov[2].iov_len)
#define msgv   (iov[2].iov_base)
#define msgc   ((char*)(iov[2].iov_base))
#define msgptr (&(iov[2].iov_base))

        if (!logmode)
                return;

        /* Prevent "derefing type-punned ptr will break aliasing rules" */
        used = vasprintf((char**)(void*)msgptr, s, p);
        if (used < 0)
                return;

        /* This is ugly and costs +60 bytes compared to multiple
         * fprintf's, but is guaranteed to do a single write.
         * This is needed for e.g. httpd logging, when multiple
         * children can produce log messages simultaneously. */

        strerr_len = strerr ? strlen(strerr) : 0;
        msgeol_len = strlen(msg_eol);
        /* +3 is for ": " before strerr and for terminating NUL */
        msgv = xrealloc(msgv, used + strerr_len + msgeol_len + 3);
        if (strerr) {
                msgc[used++] = ':';
                msgc[used++] = ' ';
                strcpy(msgc + used, strerr);
                used += strerr_len;
        }
        strcpy(msgc + used, msg_eol);
        used += msgeol_len;

        if (logmode & LOGMODE_STDIO) {
                iov[0].iov_base = (char*)applet_name;
                iov[0].iov_len = strlen(applet_name);
                iov[1].iov_base = (char*)": ";
                iov[1].iov_len = 2;
                /*iov[2].iov_base = msgc;*/
                /*iov[2].iov_len = used;*/
                fflush_all();
                writev(STDERR_FILENO, iov, 3);
        }
# if ENABLE_FEATURE_SYSLOG
        if (logmode & LOGMODE_SYSLOG) {
                syslog(syslog_level, "%s", msgc);
        }
# endif
        free(msgc);
}
#endif


void FAST_FUNC bb_error_msg_and_die(const char *s, ...)
{
        va_list p;

        va_start(p, s);
        bb_verror_msg(s, p, NULL);
        va_end(p);
        xfunc_die();
}

void FAST_FUNC bb_error_msg(const char *s, ...)
{
        va_list p;

        va_start(p, s);
        bb_verror_msg(s, p, NULL);
        va_end(p);
}

#if ENABLE_FEATURE_SYSLOG_INFO
void FAST_FUNC bb_vinfo_msg(const char *s, va_list p)
{
        syslog_level = LOG_INFO;
        bb_verror_msg(s, p, NULL);
        syslog_level = LOG_ERR;
}

void FAST_FUNC bb_info_msg(const char *s, ...)
{
        va_list p;

        va_start(p, s);
        bb_vinfo_msg(s, p);
        va_end(p);
}

void FAST_FUNC bb_simple_info_msg(const char *s)
{
        bb_info_msg("%s", s);
}
#endif

void FAST_FUNC bb_simple_error_msg(const char *s)
{
        bb_error_msg("%s", s);
}

void FAST_FUNC bb_simple_error_msg_and_die(const char *s)
{
        bb_error_msg_and_die("%s", s);
}