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diff --git a/src/include/libplacebo/log.h b/src/include/libplacebo/log.h
new file mode 100644
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+++ b/src/include/libplacebo/log.h
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+/*
+ * This file is part of libplacebo.
+ *
+ * libplacebo is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * libplacebo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with libplacebo.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LIBPLACEBO_LOG_H_
+#define LIBPLACEBO_LOG_H_
+
+#include <libplacebo/config.h>
+#include <libplacebo/common.h>
+
+PL_API_BEGIN
+
+// The log level associated with a given log message.
+enum pl_log_level {
+    PL_LOG_NONE = 0,
+    PL_LOG_FATAL,   // results in total loss of function of a major component
+    PL_LOG_ERR,     // serious error; may result in degraded function
+    PL_LOG_WARN,    // warning; potentially bad, probably user-relevant
+    PL_LOG_INFO,    // informational message, also potentially harmless errors
+    PL_LOG_DEBUG,   // verbose debug message, informational
+    PL_LOG_TRACE,   // very noisy trace of activity,, usually benign
+    PL_LOG_ALL = PL_LOG_TRACE,
+};
+
+struct pl_log_params {
+    // Logging callback. All messages, informational or otherwise, will get
+    // redirected to this callback. The logged messages do not include trailing
+    // newlines. Optional.
+    void (*log_cb)(void *log_priv, enum pl_log_level level, const char *msg);
+    void *log_priv;
+
+    // The current log level. Controls the level of message that will be
+    // redirected to the log callback. Setting this to PL_LOG_ALL means all
+    // messages will be forwarded, but doing so indiscriminately can result
+    // in increased CPU usage as it may enable extra debug paths based on the
+    // configured log level.
+    enum pl_log_level log_level;
+};
+
+#define pl_log_params(...) (&(struct pl_log_params) { __VA_ARGS__ })
+PL_API extern const struct pl_log_params pl_log_default_params;
+
+// Thread-safety: Safe
+//
+// Note: In any context in which `pl_log` is used, users may also pass NULL
+// to disable logging. In other words, NULL is a valid `pl_log`.
+typedef const struct pl_log_t {
+    struct pl_log_params params;
+} *pl_log;
+
+#define pl_log_glue1(x, y) x##y
+#define pl_log_glue2(x, y) pl_log_glue1(x, y)
+// Force a link error in the case of linking against an incompatible API
+// version.
+#define pl_log_create pl_log_glue2(pl_log_create_, PL_API_VER)
+// Creates a pl_log. `api_ver` is for historical reasons and ignored currently.
+// `params` defaults to `&pl_log_default_params` if left as NULL.
+//
+// Note: As a general rule, any `params` struct used as an argument to a
+// function need only live until the corresponding function returns.
+PL_API pl_log pl_log_create(int api_ver, const struct pl_log_params *params);
+
+// Destroy a `pl_log` object.
+//
+// Note: As a general rule, all `_destroy` functions take the pointer to the
+// object to free as their parameter. This pointer is overwritten by NULL
+// afterwards. Calling a _destroy function on &{NULL} is valid, but calling it
+// on NULL itself is invalid.
+PL_API void pl_log_destroy(pl_log *log);
+
+// Update the parameters of a `pl_log` without destroying it. This can be
+// used to change the log function, log context or log level retroactively.
+// `params` defaults to `&pl_log_default_params` if left as NULL.
+//
+// Returns the previous params, atomically.
+PL_API struct pl_log_params pl_log_update(pl_log log, const struct pl_log_params *params);
+
+// Like `pl_log_update` but only updates the log level, leaving the log
+// callback intact.
+//
+// Returns the previous log level, atomically.
+PL_API enum pl_log_level pl_log_level_update(pl_log log, enum pl_log_level level);
+
+// Two simple, stream-based loggers. You can use these as the log_cb. If you
+// also set log_priv to a FILE* (e.g. stdout or stderr) it will be printed
+// there; otherwise, it will be printed to stdout or stderr depending on the
+// log level.
+//
+// The version with colors will use ANSI escape sequences to indicate the log
+// level. The version without will use explicit prefixes.
+PL_API void pl_log_simple(void *stream, enum pl_log_level level, const char *msg);
+PL_API void pl_log_color(void *stream, enum pl_log_level level, const char *msg);
+
+// Backwards compatibility with older versions of libplacebo
+#define pl_context pl_log
+#define pl_context_params pl_log_params
+
+PL_API_END
+
+#endif // LIBPLACEBO_LOG_H_