/*
 * Copyright (C) 2016 Red Hat
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 * Rob Clark <robdclark@gmail.com>
 */

#ifndef DEBUG
#define DEBUG /* for pr_debug() */
#endif

#include <linux/seq_file.h>
#include <drm/drmP.h>
#include <drm/drm_print.h>

void __drm_puts_coredump(struct drm_printer *p, const char *str)
{
        struct drm_print_iterator *iterator = p->arg;
        ssize_t len;

        if (!iterator->remain)
                return;

        if (iterator->offset < iterator->start) {
                ssize_t copy;

                len = strlen(str);

                if (iterator->offset + len <= iterator->start) {
                        iterator->offset += len;
                        return;
                }

                copy = len - (iterator->start - iterator->offset);

                if (copy > iterator->remain)
                        copy = iterator->remain;

                /* Copy out the bit of the string that we need */
                memcpy(iterator->data,
                        str + (iterator->start - iterator->offset), copy);

                iterator->offset = iterator->start + copy;
                iterator->remain -= copy;
        } else {
                ssize_t pos = iterator->offset - iterator->start;

                len = min_t(ssize_t, strlen(str), iterator->remain);

                memcpy(iterator->data + pos, str, len);

                iterator->offset += len;
                iterator->remain -= len;
        }
}
EXPORT_SYMBOL(__drm_puts_coredump);

void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
{
        kvprintf(vaf->fmt, *vaf->va);
#if 0
        struct drm_print_iterator *iterator = p->arg;
        size_t len;
        char *buf;

        if (!iterator->remain)
                return;

        /* Figure out how big the string will be */
        len = snprintf(NULL, 0, "%pV", vaf);

        /* This is the easiest path, we've already advanced beyond the offset */
        if (iterator->offset + len <= iterator->start) {
                iterator->offset += len;
                return;
        }

        /* Then check if we can directly copy into the target buffer */
        if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
                ssize_t pos = iterator->offset - iterator->start;

                snprintf(((char *) iterator->data) + pos,
                        iterator->remain, "%pV", vaf);

                iterator->offset += len;
                iterator->remain -= len;

                return;
        }

        /*
         * Finally, hit the slow path and make a temporary string to copy over
         * using _drm_puts_coredump
         */
        buf = kmalloc(len + 1, M_DRM, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
        if (!buf)
                return;

        snprintf(buf, len + 1, "%pV", vaf);
        __drm_puts_coredump(p, (const char *) buf);

        kfree(buf);
#endif
}
EXPORT_SYMBOL(__drm_printfn_coredump);

void __drm_puts_seq_file(struct drm_printer *p, const char *str)
{
#ifdef __DragonFly__
        seq_puts((struct seq_file *)(p->arg), str);
#else
        seq_puts(p->arg, str);
#endif
}
EXPORT_SYMBOL(__drm_puts_seq_file);

void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
{
        seq_printf(p->arg, "%pV", vaf);
}
EXPORT_SYMBOL(__drm_printfn_seq_file);

void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
{
        dev_info(p->arg, "[" DRM_NAME "]");
        kvprintf(vaf->fmt, *vaf->va);
}
EXPORT_SYMBOL(__drm_printfn_info);

void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf)
{
        pr_debug("%s ", p->prefix);
        kvprintf(vaf->fmt, *vaf->va);
}
EXPORT_SYMBOL(__drm_printfn_debug);

/**
 * drm_puts - print a const string to a &drm_printer stream
 * @p: the &drm printer
 * @str: const string
 *
 * Allow &drm_printer types that have a constant string
 * option to use it.
 */
void drm_puts(struct drm_printer *p, const char *str)
{
        if (p->puts)
                p->puts(p, str);
        else
                drm_printf(p, "%s", str);
}
EXPORT_SYMBOL(drm_puts);

/**
 * drm_printf - print to a &drm_printer stream
 * @p: the &drm_printer
 * @f: format string
 */
void drm_printf(struct drm_printer *p, const char *f, ...)
{
        va_list args;

        va_start(args, f);
        drm_vprintf(p, f, &args);
        va_end(args);
}
EXPORT_SYMBOL(drm_printf);

void drm_dev_printk(const char *func, const struct device *dev,
                    const char *level, char *format, ...)
{
#if 0
        struct va_format vaf;
#endif
        va_list args;

        va_start(args, format);
#if 0
        vaf.fmt = format;
        vaf.va = &args;
#endif

#if 0
        if (dev)
                dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
                           __builtin_return_address(0), &vaf);
        else
                printk("%s" "[" DRM_NAME ":%ps] %pV",
                       level, __builtin_return_address(0), &vaf);
#else
        if (dev) {
                if (unlikely(drm_debug & DRM_UT_PID)) {
                        dev_printk(level, dev, "[" DRM_NAME ":pid%d:%s] ",
                                   DRM_CURRENTPID, func);
                } else {
                        dev_printk(level, dev, "[" DRM_NAME ":%s] ",
                                   func);
                }
                kvprintf(format, args);
        } else {
                if (unlikely(drm_debug & DRM_UT_PID)) {
                        printk("%s" "[" DRM_NAME ":pid%d:%s] ",
                               level, DRM_CURRENTPID, func);
                } else {
                        printk("%s" "[" DRM_NAME ":%s] ",
                               level, func);
                }
                kvprintf(format, args);
        }
#endif

        va_end(args);
}
EXPORT_SYMBOL(drm_dev_printk);

void drm_dev_dbg(const char *func, const struct device *dev,
                 unsigned int category, char *format, ...)
{
#if 0
        struct va_format vaf;
#endif
        va_list args;

        if (!(drm_debug & category))
                return;

        va_start(args, format);
#if 0
        vaf.fmt = format;
        vaf.va = &args;
#endif

#if 0
        if (dev)
                dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%ps] %pV",
                           __builtin_return_address(0), &vaf);
        else
                printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
                       __builtin_return_address(0), &vaf);
#else
        if (dev) {
                if (unlikely(drm_debug & DRM_UT_PID)) {
                        dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":pid%d:%s] ",
                                   DRM_CURRENTPID, func);
                } else {
                        dev_printk(KERN_DEBUG, dev, "[" DRM_NAME ":%s] ",
                                   func);
                }
                kvprintf(format, args);
        } else {
                if (unlikely(drm_debug & DRM_UT_PID)) {
                        printk(KERN_DEBUG "[" DRM_NAME ":pid%d:%s] ",
                               DRM_CURRENTPID, func);
                } else {
                        printk(KERN_DEBUG "[" DRM_NAME ":%s] ",
                               func);
                }
                kvprintf(format, args);
        }
#endif

        va_end(args);
}
EXPORT_SYMBOL(drm_dev_dbg);

void drm_dbg(const char *func, unsigned int category, const char *format, ...)
{
#if 0
        struct va_format vaf;
#endif
        va_list args;

        if (!(drm_debug & category))
                return;

        va_start(args, format);
#if 0
        vaf.fmt = format;
        vaf.va = &args;
#endif

#if 0
        printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV",
               __builtin_return_address(0), &vaf);
#else
        if (unlikely(drm_debug & DRM_UT_PID)) {
                printk(KERN_DEBUG "[" DRM_NAME ":pid%d:%s] ",
                       DRM_CURRENTPID, func);
        } else {
                printk(KERN_DEBUG "[" DRM_NAME ":%s] ",
                       func);
        }
        kvprintf(format, args);
#endif

        va_end(args);
}
EXPORT_SYMBOL(drm_dbg);

void drm_err(const char *func, const char *format, ...)
{
#if 0
        struct va_format vaf;
#endif
        va_list args;

        va_start(args, format);
#if 0
        vaf.fmt = format;
        vaf.va = &args;
#endif

#if 0
        printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
               __builtin_return_address(0), &vaf);
#else
        if (unlikely(drm_debug & DRM_UT_PID)) {
                printk(KERN_ERR "[" DRM_NAME ":pid%d:%s] *ERROR* ",
                       DRM_CURRENTPID, func);
        } else {
                printk(KERN_ERR "[" DRM_NAME ":%s] *ERROR* ",
                       func);
        }
        kvprintf(format, args);
#endif

        va_end(args);
}
EXPORT_SYMBOL(drm_err);