From 37be40a94aef84ada3a43f20e6e3244ef0f8fa9a Mon Sep 17 00:00:00 2001 From: MyungJoo Ham Date: Fri, 3 Jul 2020 10:05:23 +0900 Subject: [PATCH] [Tools] GstPipe String Parser Rather than rewriting lex/yacc code from scratch for python, modify GST's lex/yacc (flex/bison) C code and call it from python. This is the first commit of parser and simply imports GST-Parser code without touching it. Signed-off-by: MyungJoo Ham --- tools/development/parser/.gitignore | 12 + tools/development/parser/gen_grammar.py.in | 21 + tools/development/parser/gen_lex.py.in | 27 + tools/development/parser/grammar.y | 1223 ++++++++++++++++++++++++++++ tools/development/parser/meson.build | 71 ++ tools/development/parser/parse.l | 163 ++++ tools/development/parser/types.h | 124 +++ 7 files changed, 1641 insertions(+) create mode 100644 tools/development/parser/.gitignore create mode 100755 tools/development/parser/gen_grammar.py.in create mode 100755 tools/development/parser/gen_lex.py.in create mode 100644 tools/development/parser/grammar.y create mode 100644 tools/development/parser/meson.build create mode 100644 tools/development/parser/parse.l create mode 100644 tools/development/parser/types.h diff --git a/tools/development/parser/.gitignore b/tools/development/parser/.gitignore new file mode 100644 index 0000000..5faa3b3 --- /dev/null +++ b/tools/development/parser/.gitignore @@ -0,0 +1,12 @@ +grammar +grammar.output +grammar.tab.c +grammar.tab.h +lex.yy.c +parse.c +parse_lex.h +lex.priv_gst_parse_yy.c +*.bb +*.bbg +*.da +*.gcno diff --git a/tools/development/parser/gen_grammar.py.in b/tools/development/parser/gen_grammar.py.in new file mode 100755 index 0000000..3a7af00 --- /dev/null +++ b/tools/development/parser/gen_grammar.py.in @@ -0,0 +1,21 @@ +#!/usr/bin/env python3 + +import subprocess, sys, shlex + +cfile = sys.argv[1] +hfile = sys.argv[2] +yfile = sys.argv[3] + +args = ['-d', '-v', '-ppriv_gst_parse_yy', yfile, '-o', cfile] +bison = [r'@BISON@'] + shlex.split(r'@BISON_ARGS@') +subprocess.check_call(bison + args) + +prefix = ''' +#ifdef HAVE_CONFIG_H +#include +#endif +''' + +contents = open(cfile).read() +content = prefix + contents +open(cfile, 'w').write(contents) diff --git a/tools/development/parser/gen_lex.py.in b/tools/development/parser/gen_lex.py.in new file mode 100755 index 0000000..e8c6844 --- /dev/null +++ b/tools/development/parser/gen_lex.py.in @@ -0,0 +1,27 @@ +#!/usr/bin/env python3 + +import subprocess, sys, shlex + +cfile = sys.argv[1] +hfile = sys.argv[2] +lfile = sys.argv[3] +tabhfile = sys.argv[4] + +args = ['--header-file=' + hfile, '-o', cfile, '-Ppriv_gst_parse_yy', lfile] +flex = [r'@FLEX@'] + shlex.split(r'@FLEX_ARGS@') +subprocess.check_call(flex + args) + +prefix = '''#ifdef HAVE_CONFIG_H +#include +#endif +''' +parse_snippet = '''void priv_gst_parse_yyset_column (int column_no , void * yyscanner); +void priv_gst_parse_yyset_column (int column_no , void * yyscanner) +''' + +contents = open(cfile).read() +if not 'priv_gst_parse_yyget_column' in contents: + contents = parse_snippet + contents +contents = prefix + contents + +open(cfile, 'w').write(contents) diff --git a/tools/development/parser/grammar.y b/tools/development/parser/grammar.y new file mode 100644 index 0000000..e789d33 --- /dev/null +++ b/tools/development/parser/grammar.y @@ -0,0 +1,1223 @@ +%{ +/* SPDX-License-Identifier: LGPL-2.1-only */ +/** + * This is imported from GStreamer and altered to parse GST-Pipeline + */ + +#include +#include +#include +#include +#include +#include "types.h" + +/* All error messages in this file are user-visible and need to be translated. + * Don't start the message with a capital, and don't end them with a period, + * as they will be presented inside a sentence/error. + */ + +#define YYERROR_VERBOSE 1 + +#define YYENABLE_NLS 0 + +#ifndef YYLTYPE_IS_TRIVIAL +#define YYLTYPE_IS_TRIVIAL 0 +#endif + +/******************************************************************************************* +*** define SET_ERROR macro/function +*******************************************************************************************/ +#ifdef G_HAVE_ISO_VARARGS + +# define SET_ERROR(error, type, ...) \ +G_STMT_START { \ + GST_CAT_ERROR (GST_CAT_PIPELINE, __VA_ARGS__); \ + if ((error) && !*(error)) { \ + g_set_error ((error), GST_PARSE_ERROR, (type), __VA_ARGS__); \ + } \ +} G_STMT_END + +#elif defined(G_HAVE_GNUC_VARARGS) + +# define SET_ERROR(error, type, args...) \ +G_STMT_START { \ + GST_CAT_ERROR (GST_CAT_PIPELINE, args ); \ + if ((error) && !*(error)) { \ + g_set_error ((error), GST_PARSE_ERROR, (type), args ); \ + } \ +} G_STMT_END + +#else + +static inline void +SET_ERROR (GError **error, gint type, const char *format, ...) +{ + if (error) { + if (*error) { + g_warning ("error while parsing"); + } else { + va_list varargs; + char *string; + + va_start (varargs, format); + string = g_strdup_vprintf (format, varargs); + va_end (varargs); + + g_set_error (error, GST_PARSE_ERROR, type, string); + + g_free (string); + } + } +} + +#endif /* G_HAVE_ISO_VARARGS */ + +/*** define YYPRINTF macro/function if we're debugging */ + +/* bison 1.35 calls this macro with side effects, we need to make sure the + side effects work - crappy bison */ + +#ifndef GST_DISABLE_GST_DEBUG +# define YYDEBUG 1 + +# ifdef G_HAVE_ISO_VARARGS + +/* # define YYFPRINTF(a, ...) GST_CAT_DEBUG (GST_CAT_PIPELINE, __VA_ARGS__) */ +# define YYFPRINTF(a, ...) \ +G_STMT_START { \ + GST_CAT_LOG (GST_CAT_PIPELINE, __VA_ARGS__); \ +} G_STMT_END + +# elif defined(G_HAVE_GNUC_VARARGS) + +# define YYFPRINTF(a, args...) \ +G_STMT_START { \ + GST_CAT_LOG (GST_CAT_PIPELINE, args); \ +} G_STMT_END + +# else + +static inline void +YYPRINTF(const char *format, ...) +{ + va_list varargs; + gchar *temp; + + va_start (varargs, format); + temp = g_strdup_vprintf (format, varargs); + GST_CAT_LOG (GST_CAT_PIPELINE, "%s", temp); + g_free (temp); + va_end (varargs); +} + +# endif /* G_HAVE_ISO_VARARGS */ + +#endif /* GST_DISABLE_GST_DEBUG */ + + +/* + * include headers generated by bison & flex, after defining (or not defining) YYDEBUG + */ +#include "grammar.tab.h" +#include "parse_lex.h" + +/******************************************************************************************* +*** report missing elements/bins/.. +*******************************************************************************************/ + + +static void add_missing_element(graph_t *graph,gchar *name){ + if ((graph)->ctx){ + (graph)->ctx->missing_elements = g_list_append ((graph)->ctx->missing_elements, g_strdup (name)); + } +} + + +/******************************************************************************************* +*** helpers for pipeline-setup +*******************************************************************************************/ + +#define TRY_SETUP_LINK(l) G_STMT_START { \ + if( (!(l)->src.element) && (!(l)->src.name) ){ \ + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, _("link has no source [sink=%s@%p]"), \ + (l)->sink.name ? (l)->sink.name : "", \ + (l)->sink.element); \ + gst_parse_free_link (l); \ + }else if( (!(l)->sink.element) && (!(l)->sink.name) ){ \ + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, _("link has no sink [source=%s@%p]"), \ + (l)->src.name ? (l)->src.name : "", \ + (l)->src.element); \ + gst_parse_free_link (l); \ + }else{ \ + graph->links = g_slist_append (graph->links, l ); \ + } \ +} G_STMT_END + +typedef struct { + gchar *src_pad; + gchar *sink_pad; + GstElement *sink; + GstCaps *caps; + gulong pad_added_signal_id, no_more_pads_signal_id; + gboolean all_pads; +} DelayedLink; + +typedef struct { + gchar *name; + gchar *value_str; + gulong signal_id; +} DelayedSet; + +static int gst_resolve_reference(reference_t *rr, GstElement *pipeline){ + GstBin *bin; + + if(rr->element) return 0; /* already resolved! */ + if(!rr->name) return -2; /* no chance! */ + + if (GST_IS_BIN (pipeline)){ + bin = GST_BIN (pipeline); + rr->element = gst_bin_get_by_name_recurse_up (bin, rr->name); + } else { + rr->element = strcmp (GST_ELEMENT_NAME (pipeline), rr->name) == 0 ? + gst_object_ref(pipeline) : NULL; + } + if(rr->element) return 0; /* resolved */ + else return -1; /* not found */ +} + +static void gst_parse_free_delayed_set (DelayedSet *set) +{ + g_free(set->name); + g_free(set->value_str); + g_slice_free(DelayedSet, set); +} + +static void gst_parse_new_child(GstChildProxy *child_proxy, GObject *object, + const gchar * name, gpointer data); + +static void gst_parse_add_delayed_set (GstElement *element, gchar *name, gchar *value_str) +{ + DelayedSet *data = g_slice_new0 (DelayedSet); + + GST_CAT_LOG_OBJECT (GST_CAT_PIPELINE, element, "delaying property set %s to %s", + name, value_str); + + data->name = g_strdup(name); + data->value_str = g_strdup(value_str); + data->signal_id = g_signal_connect_data(element, "child-added", + G_CALLBACK (gst_parse_new_child), data, (GClosureNotify) + gst_parse_free_delayed_set, (GConnectFlags) 0); + + /* FIXME: we would need to listen on all intermediate bins too */ + if (GST_IS_BIN (element)) { + gchar **names, **current; + GstElement *parent, *child; + + current = names = g_strsplit (name, "::", -1); + parent = gst_bin_get_by_name (GST_BIN_CAST (element), current[0]); + current++; + while (parent && current[0]) { + child = gst_bin_get_by_name (GST_BIN (parent), current[0]); + if (!child && current[1]) { + char *sub_name = g_strjoinv ("::", ¤t[0]); + + gst_parse_add_delayed_set(parent, sub_name, value_str); + g_free (sub_name); + } + gst_object_unref (parent); + parent = child; + current++; + } + if (parent) + gst_object_unref (parent); + g_strfreev (names); + } +} + +static void gst_parse_new_child(GstChildProxy *child_proxy, GObject *object, + const gchar * name, gpointer data) +{ + DelayedSet *set = (DelayedSet *) data; + GParamSpec *pspec; + GValue v = { 0, }; + GObject *target = NULL; + GType value_type; + + GST_CAT_LOG_OBJECT (GST_CAT_PIPELINE, child_proxy, "new child %s, checking property %s", + name, set->name); + + if (gst_child_proxy_lookup (child_proxy, set->name, &target, &pspec)) { + gboolean got_value = FALSE; + + value_type = pspec->value_type; + + GST_CAT_LOG_OBJECT (GST_CAT_PIPELINE, child_proxy, "parsing delayed property %s as a %s from %s", + pspec->name, g_type_name (value_type), set->value_str); + g_value_init (&v, value_type); + if (gst_value_deserialize (&v, set->value_str)) + got_value = TRUE; + else if (g_type_is_a (value_type, GST_TYPE_ELEMENT)) { + GstElement *bin; + + bin = gst_parse_bin_from_description_full (set->value_str, TRUE, NULL, + GST_PARSE_FLAG_NO_SINGLE_ELEMENT_BINS | GST_PARSE_FLAG_PLACE_IN_BIN, NULL); + if (bin) { + g_value_set_object (&v, bin); + got_value = TRUE; + } + } + g_signal_handler_disconnect (child_proxy, set->signal_id); + if (!got_value) + goto error; + g_object_set_property (target, pspec->name, &v); + } else { + const gchar *obj_name = GST_OBJECT_NAME(object); + gint len = strlen (obj_name); + + /* do a delayed set */ + if ((strlen (set->name) > (len + 2)) && !strncmp (set->name, obj_name, len) && !strncmp (&set->name[len], "::", 2)) { + gst_parse_add_delayed_set (GST_ELEMENT(child_proxy), set->name, set->value_str); + } + } + +out: + if (G_IS_VALUE (&v)) + g_value_unset (&v); + if (target) + g_object_unref (target); + return; + +error: + GST_CAT_ERROR (GST_CAT_PIPELINE, "could not set property \"%s\" in %" + GST_PTR_FORMAT, pspec->name, target); + goto out; +} + +static void gst_parse_element_set (gchar *value, GstElement *element, graph_t *graph) +{ + GParamSpec *pspec = NULL; + gchar *pos = value; + GValue v = { 0, }; + GObject *target = NULL; + GType value_type; + + /* do nothing if assignment is for missing element */ + if (element == NULL) + goto out; + + /* parse the string, so the property name is null-terminated and pos points + to the beginning of the value */ + while (!g_ascii_isspace (*pos) && (*pos != '=')) pos++; + if (*pos == '=') { + *pos = '\0'; + } else { + *pos = '\0'; + pos++; + while (g_ascii_isspace (*pos)) pos++; + } + pos++; + while (g_ascii_isspace (*pos)) pos++; + /* truncate a string if it is delimited with double quotes */ + if (*pos == '"' && pos[strlen (pos) - 1] == '"') { + pos++; + pos[strlen (pos) - 1] = '\0'; + } + gst_parse_unescape (pos); + + if (GST_IS_CHILD_PROXY (element)) { + if (!gst_child_proxy_lookup (GST_CHILD_PROXY (element), value, &target, &pspec)) { + /* do a delayed set */ + gst_parse_add_delayed_set (element, value, pos); + } + } else { + pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (element), value); + if (pspec != NULL) { + target = G_OBJECT (g_object_ref (element)); + GST_CAT_LOG_OBJECT (GST_CAT_PIPELINE, target, "found %s property", value); + } else { + SET_ERROR (graph->error, GST_PARSE_ERROR_NO_SUCH_PROPERTY, \ + _("no property \"%s\" in element \"%s\""), value, \ + GST_ELEMENT_NAME (element)); + } + } + + if (pspec != NULL && target != NULL) { + gboolean got_value = FALSE; + + value_type = pspec->value_type; + + GST_CAT_LOG_OBJECT (GST_CAT_PIPELINE, element, "parsing property %s as a %s", + pspec->name, g_type_name (value_type)); + + g_value_init (&v, value_type); + if (gst_value_deserialize (&v, pos)) + got_value = TRUE; + else if (g_type_is_a (value_type, GST_TYPE_ELEMENT)) { + GstElement *bin; + + bin = gst_parse_bin_from_description_full (pos, TRUE, NULL, + GST_PARSE_FLAG_NO_SINGLE_ELEMENT_BINS | GST_PARSE_FLAG_PLACE_IN_BIN, NULL); + if (bin) { + g_value_set_object (&v, bin); + got_value = TRUE; + } + } + if (!got_value) + goto error; + g_object_set_property (target, pspec->name, &v); + } + +out: + gst_parse_strfree (value); + if (G_IS_VALUE (&v)) + g_value_unset (&v); + if (target) + g_object_unref (target); + return; + +error: + SET_ERROR (graph->error, GST_PARSE_ERROR_COULD_NOT_SET_PROPERTY, + _("could not set property \"%s\" in element \"%s\" to \"%s\""), + value, GST_ELEMENT_NAME (element), pos); + goto out; +} + +static void gst_parse_free_reference (reference_t *rr) +{ + if(rr->element) gst_object_unref(rr->element); + gst_parse_strfree (rr->name); + g_slist_foreach (rr->pads, (GFunc) gst_parse_strfree, NULL); + g_slist_free (rr->pads); +} + +static void gst_parse_free_link (link_t *link) +{ + gst_parse_free_reference (&(link->src)); + gst_parse_free_reference (&(link->sink)); + if (link->caps) gst_caps_unref (link->caps); + gst_parse_link_free (link); +} + +static void gst_parse_free_chain (chain_t *ch) +{ + GSList *walk; + gst_parse_free_reference (&(ch->first)); + gst_parse_free_reference (&(ch->last)); + for(walk=ch->elements;walk;walk=walk->next) + gst_object_unref (walk->data); + g_slist_free (ch->elements); + gst_parse_chain_free (ch); +} + +static void gst_parse_free_delayed_link (DelayedLink *link) +{ + g_free (link->src_pad); + g_free (link->sink_pad); + if (link->caps) gst_caps_unref (link->caps); + g_slice_free (DelayedLink, link); +} + +#define PRETTY_PAD_NAME_FMT "%s %s of %s named %s" +#define PRETTY_PAD_NAME_ARGS(elem, pad_name) \ + (pad_name ? "pad " : "some"), (pad_name ? pad_name : "pad"), \ + G_OBJECT_TYPE_NAME(elem), GST_STR_NULL (GST_ELEMENT_NAME (elem)) + +static void gst_parse_no_more_pads (GstElement *src, gpointer data) +{ + DelayedLink *link = data; + + /* Don't warn for all-pads links, as we expect those to + * still be active at no-more-pads */ + if (!link->all_pads) { + GST_ELEMENT_WARNING(src, PARSE, DELAYED_LINK, + (_("Delayed linking failed.")), + ("failed delayed linking " PRETTY_PAD_NAME_FMT " to " PRETTY_PAD_NAME_FMT, + PRETTY_PAD_NAME_ARGS (src, link->src_pad), + PRETTY_PAD_NAME_ARGS (link->sink, link->sink_pad))); + } + /* we keep the handlers connected, so that in case an element still adds a pad + * despite no-more-pads, we will consider it for pending delayed links */ +} + +static void gst_parse_found_pad (GstElement *src, GstPad *pad, gpointer data) +{ + DelayedLink *link = data; + + GST_CAT_INFO (GST_CAT_PIPELINE, + "trying delayed linking %s " PRETTY_PAD_NAME_FMT " to " PRETTY_PAD_NAME_FMT, + link->all_pads ? "all pads" : "one pad", + PRETTY_PAD_NAME_ARGS (src, link->src_pad), + PRETTY_PAD_NAME_ARGS (link->sink, link->sink_pad)); + + if (gst_element_link_pads_filtered (src, link->src_pad, link->sink, + link->sink_pad, link->caps)) { + /* do this here, we don't want to get any problems later on when + * unlocking states */ + GST_CAT_DEBUG (GST_CAT_PIPELINE, + "delayed linking %s " PRETTY_PAD_NAME_FMT " to " PRETTY_PAD_NAME_FMT " worked", + link->all_pads ? "all pads" : "one pad", + PRETTY_PAD_NAME_ARGS (src, link->src_pad), + PRETTY_PAD_NAME_ARGS (link->sink, link->sink_pad)); + g_signal_handler_disconnect (src, link->no_more_pads_signal_id); + /* releases 'link' */ + if (!link->all_pads) + g_signal_handler_disconnect (src, link->pad_added_signal_id); + } +} + +/* both padnames and the caps may be NULL */ +static gboolean +gst_parse_perform_delayed_link (GstElement *src, const gchar *src_pad, + GstElement *sink, const gchar *sink_pad, + GstCaps *caps, gboolean all_pads) +{ + GList *templs = gst_element_class_get_pad_template_list ( + GST_ELEMENT_GET_CLASS (src)); + + for (; templs; templs = templs->next) { + GstPadTemplate *templ = (GstPadTemplate *) templs->data; + if ((GST_PAD_TEMPLATE_DIRECTION (templ) == GST_PAD_SRC) && + (GST_PAD_TEMPLATE_PRESENCE(templ) == GST_PAD_SOMETIMES)) + { + DelayedLink *data = g_slice_new (DelayedLink); + + data->all_pads = all_pads; + + /* TODO: maybe we should check if src_pad matches this template's names */ + + GST_CAT_DEBUG (GST_CAT_PIPELINE, + "trying delayed link " PRETTY_PAD_NAME_FMT " to " PRETTY_PAD_NAME_FMT, + PRETTY_PAD_NAME_ARGS (src, src_pad), + PRETTY_PAD_NAME_ARGS (sink, sink_pad)); + + data->src_pad = g_strdup (src_pad); + data->sink = sink; + data->sink_pad = g_strdup (sink_pad); + if (caps) { + data->caps = gst_caps_copy (caps); + } else { + data->caps = NULL; + } + data->pad_added_signal_id = g_signal_connect_data (src, "pad-added", + G_CALLBACK (gst_parse_found_pad), data, + (GClosureNotify) gst_parse_free_delayed_link, (GConnectFlags) 0); + data->no_more_pads_signal_id = g_signal_connect (src, "no-more-pads", + G_CALLBACK (gst_parse_no_more_pads), data); + return TRUE; + } + } + return FALSE; +} + +static gboolean +gst_parse_element_can_do_caps (GstElement * e, GstPadDirection dir, + GstCaps * link_caps) +{ + gboolean can_do = FALSE, done = FALSE; + GstIterator *it; + + it = (dir == GST_PAD_SRC) ? gst_element_iterate_src_pads (e) : gst_element_iterate_sink_pads (e); + + while (!done && !can_do) { + GValue v = G_VALUE_INIT; + GstPad *pad; + GstCaps *caps; + + switch (gst_iterator_next (it, &v)) { + case GST_ITERATOR_OK: + pad = g_value_get_object (&v); + + caps = gst_pad_get_current_caps (pad); + if (caps == NULL) + caps = gst_pad_query_caps (pad, NULL); + + can_do = gst_caps_can_intersect (caps, link_caps); + + GST_TRACE ("can_do: %d for %" GST_PTR_FORMAT " and %" GST_PTR_FORMAT, + can_do, caps, link_caps); + + gst_caps_unref (caps); + + g_value_unset (&v); + break; + case GST_ITERATOR_DONE: + case GST_ITERATOR_ERROR: + done = TRUE; + break; + case GST_ITERATOR_RESYNC: + gst_iterator_resync (it); + break; + } + } + + gst_iterator_free (it); + + return can_do; +} + +/* + * performs a link and frees the struct. src and sink elements must be given + * return values 0 - link performed + * 1 - link delayed + * <0 - error + */ +static gint +gst_parse_perform_link (link_t *link, graph_t *graph) +{ + GstElement *src = link->src.element; + GstElement *sink = link->sink.element; + GSList *srcs = link->src.pads; + GSList *sinks = link->sink.pads; + g_assert (GST_IS_ELEMENT (src)); + g_assert (GST_IS_ELEMENT (sink)); + + GST_CAT_INFO (GST_CAT_PIPELINE, + "linking " PRETTY_PAD_NAME_FMT " to " PRETTY_PAD_NAME_FMT " (%u/%u) with caps \"%" GST_PTR_FORMAT "\"", + PRETTY_PAD_NAME_ARGS (src, link->src.name), + PRETTY_PAD_NAME_ARGS (sink, link->sink.name), + g_slist_length (srcs), g_slist_length (sinks), link->caps); + + if (!srcs || !sinks) { + gboolean found_one = gst_element_link_pads_filtered (src, + srcs ? (const gchar *) srcs->data : NULL, sink, + sinks ? (const gchar *) sinks->data : NULL, link->caps); + + if (found_one) { + if (!link->all_pads) + goto success; /* Linked one, and not an all-pads link = we're done */ + + /* Try and link more available pads */ + while (gst_element_link_pads_filtered (src, + srcs ? (const gchar *) srcs->data : NULL, sink, + sinks ? (const gchar *) sinks->data : NULL, link->caps)); + } + + /* We either didn't find any static pads, or this is a all-pads link, + * in which case watch for future pads and link those. Not a failure + * in the all-pads case if there's no sometimes pads to watch */ + if (gst_parse_perform_delayed_link (src, + srcs ? (const gchar *) srcs->data : NULL, + sink, sinks ? (const gchar *) sinks->data : NULL, link->caps, + link->all_pads) || link->all_pads) { + goto success; + } else { + goto error; + } + } + if (g_slist_length (link->src.pads) != g_slist_length (link->sink.pads)) { + goto error; + } + while (srcs && sinks) { + const gchar *src_pad = (const gchar *) srcs->data; + const gchar *sink_pad = (const gchar *) sinks->data; + srcs = g_slist_next (srcs); + sinks = g_slist_next (sinks); + if (gst_element_link_pads_filtered (src, src_pad, sink, sink_pad, + link->caps)) { + continue; + } else { + if (gst_parse_perform_delayed_link (src, src_pad, + sink, sink_pad, + link->caps, link->all_pads)) { + continue; + } else { + goto error; + } + } + } + +success: + gst_parse_free_link (link); + return 0; + +error: + if (link->caps != NULL) { + gboolean src_can_do_caps, sink_can_do_caps; + gchar *caps_str = gst_caps_to_string (link->caps); + + src_can_do_caps = + gst_parse_element_can_do_caps (src, GST_PAD_SRC, link->caps); + sink_can_do_caps = + gst_parse_element_can_do_caps (sink, GST_PAD_SINK, link->caps); + + if (!src_can_do_caps && sink_can_do_caps) { + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, + _("could not link %s to %s, %s can't handle caps %s"), + GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (sink), + GST_ELEMENT_NAME (src), caps_str); + } else if (src_can_do_caps && !sink_can_do_caps) { + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, + _("could not link %s to %s, %s can't handle caps %s"), + GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (sink), + GST_ELEMENT_NAME (sink), caps_str); + } else if (!src_can_do_caps && !sink_can_do_caps) { + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, + _("could not link %s to %s, neither element can handle caps %s"), + GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (sink), caps_str); + } else { + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, + _("could not link %s to %s with caps %s"), + GST_ELEMENT_NAME (src), GST_ELEMENT_NAME (sink), caps_str); + } + g_free (caps_str); + } else { + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, + _("could not link %s to %s"), GST_ELEMENT_NAME (src), + GST_ELEMENT_NAME (sink)); + } + gst_parse_free_link (link); + return -1; +} + + +static int yyerror (void *scanner, graph_t *graph, const char *s); +%} + +%union { + gchar *ss; + chain_t *cc; + link_t *ll; + reference_t rr; + GstElement *ee; + GSList *pp; + graph_t *gg; +} + +/* No grammar ambiguities expected, FAIL otherwise */ +%expect 0 + +%token PARSE_URL +%token IDENTIFIER +%left REF PADREF BINREF +%token ASSIGNMENT +%token LINK +%token LINK_ALL + +%type binopener +%type graph +%type chain bin chainlist openchain elementary +%type reference +%type link +%type element +%type morepads pads assignments + +%destructor { gst_parse_strfree ($$); } +%destructor { if($$) + gst_parse_free_chain($$); } +%destructor { gst_parse_free_link ($$); } +%destructor { gst_parse_free_reference(&($$));} +%destructor { gst_object_unref ($$); } +%destructor { GSList *walk; + for(walk=$$;walk;walk=walk->next) + gst_parse_strfree (walk->data); + g_slist_free ($$); } + + + +%left '(' ')' +%left ',' +%right '.' +%left '!' '=' ':' + +%lex-param { void *scanner } +%parse-param { void *scanner } +%parse-param { graph_t *graph } +%pure-parser + +%start graph +%% + +/************************************************************* +* Grammar explanation: +* _element_s are specified by an identifier of their type. +* a name can be give in the optional property-assignments +* coffeeelement +* fakesrc name=john +* identity silence=false name=frodo +* (cont'd) +**************************************************************/ +element: IDENTIFIER { $$ = gst_element_factory_make ($1, NULL); + if ($$ == NULL) { + add_missing_element(graph, $1); + SET_ERROR (graph->error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, _("no element \"%s\""), $1); + } + gst_parse_strfree ($1); + } + | element ASSIGNMENT { gst_parse_element_set ($2, $1, graph); + $$ = $1; + } + ; + +/************************************************************* +* Grammar explanation: (cont'd) +* a graph has (pure) _element_s, _bin_s and _link_s. +* since bins are special elements, bins and elements can +* be generalized as _elementary_. +* The construction of _bin_s will be discussed later. +* (cont'd) +* +**************************************************************/ +elementary: + element { $$ = gst_parse_chain_new (); + /* g_print ("@%p: CHAINing elementary\n", $$); */ + $$->first.element = $1? gst_object_ref($1) : NULL; + $$->last.element = $1? gst_object_ref($1) : NULL; + $$->first.name = $$->last.name = NULL; + $$->first.pads = $$->last.pads = NULL; + $$->elements = $1 ? g_slist_prepend (NULL, $1) : NULL; + } + | bin { $$=$1; } + ; + +/************************************************************* +* Grammar explanation: (cont'd) +* a _chain_ is a list of _elementary_s that have _link_s inbetween +* which are represented through infix-notation. +* +* fakesrc ! sometransformation ! fakesink +* +* every _link_ can be augmented with _pads_. +* +* coffeesrc .sound ! speakersink +* multisrc .movie,ads ! .projector,smallscreen multisink +* +* and every _link_ can be setup to filter media-types +* mediasrc ! audio/x-raw, signed=TRUE ! stereosink +* +* User HINT: +* if the lexer does not recognize your media-type it +* will make it an element name. that results in errors +* like +* NO SUCH ELEMENT: no element audio7x-raw +* '7' vs. '/' in https://en.wikipedia.org/wiki/QWERTZ +* +* Parsing HINT: +* in the parser we need to differ between chains that can +* be extended by more elementaries (_openchain_) and others +* that are syntactically closed (handled later in this file). +* (e.g. fakesrc ! sinkreferencename.padname) +**************************************************************/ +chain: openchain { $$=$1; + if($$->last.name){ + SET_ERROR (graph->error, GST_PARSE_ERROR_SYNTAX, + _("unexpected reference \"%s\" - ignoring"), $$->last.name); + gst_parse_strfree($$->last.name); + $$->last.name=NULL; + } + if($$->last.pads){ + SET_ERROR (graph->error, GST_PARSE_ERROR_SYNTAX, + _("unexpected pad-reference \"%s\" - ignoring"), (gchar*)$$->last.pads->data); + g_slist_foreach ($$->last.pads, (GFunc) gst_parse_strfree, NULL); + g_slist_free ($$->last.pads); + $$->last.pads=NULL; + } + } + ; + +openchain: + elementary pads { $$=$1; + $$->last.pads = g_slist_concat ($$->last.pads, $2); + /* g_print ("@%p@%p: FKI elementary pads\n", $1, $$->last.pads); */ + } + | openchain link pads elementary pads + { + $2->src = $1->last; + $2->sink = $4->first; + $2->sink.pads = g_slist_concat ($3, $2->sink.pads); + TRY_SETUP_LINK($2); + $4->first = $1->first; + $4->elements = g_slist_concat ($1->elements, $4->elements); + gst_parse_chain_free($1); + $$ = $4; + $$->last.pads = g_slist_concat ($$->last.pads, $5); + } + ; + +link: LINK { $$ = gst_parse_link_new (); + $$->all_pads = FALSE; + if ($1) { + $$->caps = gst_caps_from_string ($1); + if ($$->caps == NULL) + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, _("could not parse caps \"%s\""), $1); + gst_parse_strfree ($1); + } + } + | LINK_ALL { $$ = gst_parse_link_new (); + $$->all_pads = TRUE; + if ($1) { + $$->caps = gst_caps_from_string ($1); + if ($$->caps == NULL) + SET_ERROR (graph->error, GST_PARSE_ERROR_LINK, _("could not parse caps \"%s\""), $1); + gst_parse_strfree ($1); + } + } + ; +pads: /* NOP */ { $$ = NULL; } + | PADREF morepads { $$ = $2; + $$ = g_slist_prepend ($$, $1); + } + ; +morepads: /* NOP */ { $$ = NULL; } + | ',' IDENTIFIER morepads { $$ = g_slist_prepend ($3, $2); } + ; + +/************************************************************* +* Grammar explanation: (cont'd) +* the first and last elements of a _chain_ can be give +* as URL. This creates special elements that fit the URL. +* +* fakesrc ! http://fake-sink.org +* http://somesource.org ! fakesink +**************************************************************/ + +chain: openchain link PARSE_URL { GstElement *element = + gst_element_make_from_uri (GST_URI_SINK, $3, NULL, NULL); + /* FIXME: get and parse error properly */ + if (!element) { + SET_ERROR (graph->error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + _("no sink element for URI \"%s\""), $3); + } + $$ = $1; + $2->sink.element = element?gst_object_ref(element):NULL; + $2->src = $1->last; + TRY_SETUP_LINK($2); + $$->last.element = NULL; + $$->last.name = NULL; + $$->last.pads = NULL; + if(element) $$->elements = g_slist_append ($$->elements, element); + g_free ($3); + } + ; +openchain: + PARSE_URL { GstElement *element = + gst_element_make_from_uri (GST_URI_SRC, $1, NULL, NULL); + /* FIXME: get and parse error properly */ + if (!element) { + SET_ERROR (graph->error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + _("no source element for URI \"%s\""), $1); + } + $$ = gst_parse_chain_new (); + /* g_print ("@%p: CHAINing srcURL\n", $$); */ + $$->first.element = NULL; + $$->first.name = NULL; + $$->first.pads = NULL; + $$->last.element = element ? gst_object_ref(element):NULL; + $$->last.name = NULL; + $$->last.pads = NULL; + $$->elements = element ? g_slist_prepend (NULL, element) : NULL; + g_free($1); + } + ; + + +/************************************************************* +* Grammar explanation: (cont'd) +* the first and last elements of a _chain_ can be linked +* to a named _reference_ (with optional pads). +* +* fakesrc ! nameOfSinkElement. +* fakesrc ! nameOfSinkElement.Padname +* fakesrc ! nameOfSinkElement.Padname, anotherPad +* nameOfSource.Padname ! fakesink +**************************************************************/ + +chain: openchain link reference { $$ = $1; + $2->sink= $3; + $2->src = $1->last; + TRY_SETUP_LINK($2); + $$->last.element = NULL; + $$->last.name = NULL; + $$->last.pads = NULL; + } + ; + + +openchain: + reference { $$ = gst_parse_chain_new (); + $$->last=$1; + $$->first.element = NULL; + $$->first.name = NULL; + $$->first.pads = NULL; + $$->elements = NULL; + } + ; +reference: REF morepads { + gchar *padname = $1; + GSList *pads = $2; + if (padname) { + while (*padname != '.') padname++; + *padname = '\0'; + padname++; + if (*padname != '\0') + pads = g_slist_prepend (pads, gst_parse_strdup (padname)); + } + $$.element=NULL; + $$.name=$1; + $$.pads=pads; + } + ; + + +/************************************************************* +* Grammar explanation: (cont'd) +* a _chainlist_ is just a list of _chain_s. +* +* You can specify _link_s with named +* _reference_ on each side. That +* works already after the explanations above. +* someSourceName.Pad ! someSinkName. +* someSourceName.Pad,anotherPad ! someSinkName.Apad,Bpad +* +* If a syntax error occurs, the already finished _chain_s +* and _links_ are kept intact. +*************************************************************/ + +chainlist: /* NOP */ { $$ = NULL; } + | chainlist chain { if ($1){ + gst_parse_free_reference(&($1->last)); + gst_parse_free_reference(&($2->first)); + $2->first = $1->first; + $2->elements = g_slist_concat ($1->elements, $2->elements); + gst_parse_chain_free ($1); + } + $$ = $2; + } + | chainlist error { $$=$1; + GST_CAT_DEBUG (GST_CAT_PIPELINE,"trying to recover from syntax error"); + SET_ERROR (graph->error, GST_PARSE_ERROR_SYNTAX, _("syntax error")); + } + ; + +/************************************************************* +* Grammar explanation: (cont'd) +* _bins_ +*************************************************************/ + + +assignments: /* NOP */ { $$ = NULL; } + | ASSIGNMENT assignments { $$ = g_slist_prepend ($2, $1); } + ; + +binopener: '(' { $$ = gst_parse_strdup("bin"); } + | BINREF { $$ = $1; } + ; +bin: binopener assignments chainlist ')' { + chain_t *chain = $3; + GSList *walk; + GstBin *bin = (GstBin *) gst_element_factory_make ($1, NULL); + if (!chain) { + SET_ERROR (graph->error, GST_PARSE_ERROR_EMPTY_BIN, + _("specified empty bin \"%s\", not allowed"), $1); + chain = gst_parse_chain_new (); + chain->first.element = chain->last.element = NULL; + chain->first.name = chain->last.name = NULL; + chain->first.pads = chain->last.pads = NULL; + chain->elements = NULL; + } + if (!bin) { + add_missing_element(graph, $1); + SET_ERROR (graph->error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + _("no bin \"%s\", unpacking elements"), $1); + /* clear property-list */ + g_slist_foreach ($2, (GFunc) gst_parse_strfree, NULL); + g_slist_free ($2); + $2 = NULL; + } else { + for (walk = chain->elements; walk; walk = walk->next ) + gst_bin_add (bin, GST_ELEMENT (walk->data)); + g_slist_free (chain->elements); + chain->elements = g_slist_prepend (NULL, bin); + } + $$ = chain; + /* set the properties now + * HINT: property-list cleared above, if bin==NULL + */ + for (walk = $2; walk; walk = walk->next) + gst_parse_element_set ((gchar *) walk->data, + GST_ELEMENT (bin), graph); + g_slist_free ($2); + gst_parse_strfree ($1); + } + ; + +/************************************************************* +* Grammar explanation: (cont'd) +* _graph_ +*************************************************************/ + +graph: chainlist { $$ = graph; + $$->chain = $1; + if(!$1) { + SET_ERROR (graph->error, GST_PARSE_ERROR_EMPTY, _("empty pipeline not allowed")); + } + } + ; + +%% + + +static int +yyerror (void *scanner, graph_t *graph, const char *s) +{ + /* FIXME: This should go into the GError somehow, but how? */ + GST_WARNING ("Error during parsing: %s", s); + return -1; +} + + +GstElement * +priv_gst_parse_launch (const gchar *str, GError **error, GstParseContext *ctx, + GstParseFlags flags) +{ + graph_t g; + gchar *dstr; + GSList *walk; + GstBin *bin = NULL; + GstElement *ret; + yyscan_t scanner; + + g_return_val_if_fail (str != NULL, NULL); + g_return_val_if_fail (error == NULL || *error == NULL, NULL); + + g.chain = NULL; + g.links = NULL; + g.error = error; + g.ctx = ctx; + g.flags = flags; + +#ifdef __GST_PARSE_TRACE + GST_CAT_DEBUG (GST_CAT_PIPELINE, "TRACE: tracing enabled"); + __strings = __chains = __links = 0; +#endif /* __GST_PARSE_TRACE */ + + /* g_print("Now scanning: %s\n", str); */ + + dstr = g_strdup (str); + priv_gst_parse_yylex_init (&scanner); + priv_gst_parse_yy_scan_string (dstr, scanner); + +#if YYDEBUG + yydebug = 1; +#endif + + if (yyparse (scanner, &g) != 0) { + SET_ERROR (error, GST_PARSE_ERROR_SYNTAX, + "Unrecoverable syntax error while parsing pipeline %s", str); + + priv_gst_parse_yylex_destroy (scanner); + g_free (dstr); + + goto error1; + } + priv_gst_parse_yylex_destroy (scanner); + g_free (dstr); + + GST_CAT_DEBUG (GST_CAT_PIPELINE, "got %u elements and %u links", + g.chain ? g_slist_length (g.chain->elements) : 0, + g_slist_length (g.links)); + + /* ensure chain is not NULL */ + if (!g.chain){ + g.chain=gst_parse_chain_new (); + g.chain->elements=NULL; + g.chain->first.element=NULL; + g.chain->first.name=NULL; + g.chain->first.pads=NULL; + g.chain->last.element=NULL; + g.chain->last.name=NULL; + g.chain->last.pads=NULL; + }; + + /* ensure elements is not empty */ + if(!g.chain->elements){ + g.chain->elements= g_slist_prepend (NULL, NULL); + }; + + /* put all elements in our bin if necessary */ + if(g.chain->elements->next){ + if (flags & GST_PARSE_FLAG_PLACE_IN_BIN) + bin = GST_BIN (gst_element_factory_make ("bin", NULL)); + else + bin = GST_BIN (gst_element_factory_make ("pipeline", NULL)); + g_assert (bin); + + for (walk = g.chain->elements; walk; walk = walk->next) { + if (walk->data != NULL) + gst_bin_add (bin, GST_ELEMENT (walk->data)); + } + g_slist_free (g.chain->elements); + g.chain->elements = g_slist_prepend (NULL, bin); + } + + ret = (GstElement *) g.chain->elements->data; + g_slist_free (g.chain->elements); + g.chain->elements=NULL; + if (GST_IS_BIN (ret)) + bin = GST_BIN (ret); + gst_parse_free_chain (g.chain); + g.chain = NULL; + + + /* resolve and perform links */ + for (walk = g.links; walk; walk = walk->next) { + link_t *l = (link_t *) walk->data; + int err; + err=gst_resolve_reference( &(l->src), ret); + if (err) { + if(-1==err){ + SET_ERROR (error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + "No src-element named \"%s\" - omitting link", l->src.name); + }else{ + /* probably a missing element which we've handled already */ + SET_ERROR (error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + "No src-element found - omitting link"); + } + gst_parse_free_link (l); + continue; + } + + err=gst_resolve_reference( &(l->sink), ret); + if (err) { + if(-1==err){ + SET_ERROR (error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + "No sink-element named \"%s\" - omitting link", l->src.name); + }else{ + /* probably a missing element which we've handled already */ + SET_ERROR (error, GST_PARSE_ERROR_NO_SUCH_ELEMENT, + "No sink-element found - omitting link"); + } + gst_parse_free_link (l); + continue; + } + gst_parse_perform_link (l, &g); + } + g_slist_free (g.links); + +out: +#ifdef __GST_PARSE_TRACE + GST_CAT_DEBUG (GST_CAT_PIPELINE, + "TRACE: %u strings, %u chains and %u links left", __strings, __chains, + __links); + if (__strings || __chains || __links) { + g_warning ("TRACE: %u strings, %u chains and %u links left", __strings, + __chains, __links); + } +#endif /* __GST_PARSE_TRACE */ + + return ret; + +error1: + if (g.chain) { + gst_parse_free_chain (g.chain); + g.chain=NULL; + } + + g_slist_foreach (g.links, (GFunc)gst_parse_free_link, NULL); + g_slist_free (g.links); + + if (error) + g_assert (*error); + ret = NULL; + + goto out; +} diff --git a/tools/development/parser/meson.build b/tools/development/parser/meson.build new file mode 100644 index 0000000..b627d1c --- /dev/null +++ b/tools/development/parser/meson.build @@ -0,0 +1,71 @@ +cc = meson.get_compiler('c') + +# Find flex, configure lex generator +flex_cdata = configuration_data() + +flex_min_version='2.5.31' +flex = find_program('flex', 'win_flex') + +flexversion_res = run_command([flex, '--version']) +if flexversion_res.returncode() != 0 + error('Could not get flex version (@0@)'.format(flexversion_res.stderr())) +endif + +flexversion = flexversion_res.stdout().split('\n')[0].split(' ')[1].strip() +if flexversion.version_compare('<' + flex_min_version) + error('flex version @0@ >= @1@: NO'.format(flexversion, flex_min_version)) +else + message('flex version @0@ >= @1@: YES'.format(flexversion, flex_min_version)) +endif + +flex_cdata.set('FLEX', flex.path()) +if cc.get_id() == 'msvc' + flex_cdata.set('FLEX_ARGS', '--nounistd') +else + flex_cdata.set('FLEX_ARGS', '') +endif + +gen_lex = configure_file(input : 'gen_lex.py.in', + output : 'gen_lex.py', + configuration : flex_cdata) + +# Find bison, configure grammar generator +bison_cdata = configuration_data() + +bison_min_version='2.4' +bison = find_program('bison', 'win_bison') + +bversion_res = run_command([bison, '--version']) +if bversion_res.returncode() != 0 + error('Could not get bison version (@0@)'.format(bversion_res.stderr())) +endif + +bversion = bversion_res.stdout().split('\n')[0].split(' ')[-1].strip() +if bversion.version_compare('<' + bison_min_version) + error('bison version @0@ >= @1@: NO'.format(bversion, bison_min_version)) +else + message('bison version @0@ >= @1@: YES'.format(bversion, bison_min_version)) +endif + + + +bison_cdata.set('BISON', bison.path()) +bison_cdata.set('BISON_ARGS', '') + +gen_grammar = configure_file(input : 'gen_grammar.py.in', + output : 'gen_grammar.py', + configuration : bison_cdata) + +# Custom targets +parser = custom_target('parselex', + input : 'parse.l', + output : ['lex.priv_gst_parse_yy.c', 'parse_lex.h'], + command : [python3, gen_lex, '@OUTPUT0@', '@OUTPUT1@', '@INPUT@', 'DUMMY'] +) + +grammar = custom_target('parsegrammar', + input : 'grammar.y', + output : ['grammar.tab.c', 'grammar.tab.h'], + command : [python3, gen_grammar, '@OUTPUT0@', '@OUTPUT1@', '@INPUT@'], + depends : [parser], +) diff --git a/tools/development/parser/parse.l b/tools/development/parser/parse.l new file mode 100644 index 0000000..443ccca --- /dev/null +++ b/tools/development/parser/parse.l @@ -0,0 +1,163 @@ +%{ +/* SPDX-License-Identifier: LGPL-2.1-only */ +/** + * This is imported from GStreamer and altered to parse GST-Pipeline + */ + +#include +#include + +#include +#include + +#include "types.h" +#include "grammar.tab.h" + +#ifdef malloc +#undef malloc +#endif + +#ifdef free +#undef free +#endif + +#ifdef realloc +#undef realloc +#endif + +#define malloc g_malloc +#define free g_free +#define realloc g_realloc + +/* Override the default ECHO so as to avoid fortify warnings. Ignore the + embedded-NUL case for now. We know yytext is NUL-terminated. */ +#define ECHO g_fprintf(yyout, "%s", yytext) + +#define PRINT(...) g_printinfo (__VA_ARGS__) + +%} + +_operator [(){}.!:,;=] +_identifier [[:alnum:]_][[:alnum:]\-_%:]* + +_char ("\\".)|([^[:space:]]) +_string {_char}+|("\""([^\"]|"\\\"")*"\"")|("'"([^']|"\\\'")*"'") + +_assign [[:space:]]*"="[[:space:]]* + +_protocol [[:alpha:]][[:alnum:]+-\.]* +_url ({_protocol}"://"{_string}|["."{_identifier}]?"/"{_string})|({_protocol}"://") + +/* we must do this here, because nearly everything matches a {_string} */ +_assignment {_identifier}{_assign}{_string} + +/* get pad/element references and stuff with dots right */ +_padref "."{_identifier} +_ref {_identifier}"."{_identifier}? +_binref {_identifier}[[:space:]]*"."[[:space:]]*"(" + +/* links */ +_mimechar [[:alnum:]-] +_mimetype {_mimechar}+"/"{_mimechar}+ +_capschar ("\\".)|([^\;!]) +_capsstring {_capschar}+ +_caps {_mimetype}(","[^!]|{_capsstring})* +_link ([!:][[:space:]]*{_caps}([[:space:]]*(";"[[:space:]]*{_caps})*[[:space:]]*)*[!:])|([!:]) + +%x value +%option noyywrap +%option nounput +%option reentrant +%option bison-bridge +%option never-interactive +%option noinput +%% + +{_assignment} { + /* "=" */ + PRINT ("ASSIGNMENT: %s", yytext); + yylval->ss = g_strdup (yytext); + BEGIN (INITIAL); + return ASSIGNMENT; +} + +{_padref} { + yytext++; + PRINT ("PADREF: %s", yytext); + yylval->ss = g_strdup (yytext); + BEGIN (INITIAL); + return PADREF; +} + +{_ref} { + PRINT ("REF: %s", yytext); + yylval->ss = g_strdup (yytext); + BEGIN (INITIAL); + return REF; +} + +{_binref} { + gchar *pos = yytext; + while (!g_ascii_isspace (*pos) && (*pos != '.')) pos++; + *pos = '\0'; + PRINT ("BINREF: %s", yytext); + yylval->ss = g_strdup (yytext); + BEGIN (INITIAL); + return BINREF; +} + +{_identifier} { + PRINT ("IDENTIFIER: %s", yytext); + yylval->ss = g_strdup (yytext); + BEGIN (INITIAL); + return IDENTIFIER; +} + +{_link} { + gchar *c = yytext; + gchar op; + gboolean link_all; + + PRINT ("LINK: %s", yytext); + /* First char is a link operator */ + link_all = (*c == ':'); + c++; + if (*c) { + while (g_ascii_isspace (*c)) c++; + c = yylval->ss = g_strdup (c); + while (*c) c++; + /* Last non-space char is a link operator */ + op = *--c; + if (op != '!' && op != ':') + g_assert_not_reached (); + if (op == ':') + link_all = TRUE; + + /* Walk backward past whitespaces - what remains + * is a filter caps string, or empty */ + while (g_ascii_isspace (*--c)); + *++c = '\0'; + } else { + yylval->ss = NULL; + } + BEGIN (INITIAL); + return link_all ? LINK_ALL : LINK; +} +{_url} { + PRINT ("URL: %s", yytext); + yylval->ss = g_strdup (yytext); + gst_parse_unescape (yylval->ss); + BEGIN (INITIAL); + return PARSE_URL; +} + +{_operator} { PRINT ("OPERATOR: [%s]", yytext); return *yytext; } + +[[:space:]]+ { PRINT ("SPACE: [%s]", yytext); } + +. { + PRINT ("Invalid Lexer element: %s\n", yytext); + return *yytext; +} + +%% diff --git a/tools/development/parser/types.h b/tools/development/parser/types.h new file mode 100644 index 0000000..9743c7d --- /dev/null +++ b/tools/development/parser/types.h @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: LGPL-2.1-only */ +/** + * This is imported from GStreamer and altered to parse GST-Pipeline + * + * @file types.h + * @date 12 Nov 2020 + * @brief GST-Parser's types.h modified for gst2pbtxt parser (nnstreamer parser) + * @see https://github.com/nnstreamer/nnstreamer + * @author MyungJoo Ham + * @bug No known bugs except for NYI items + */ +#ifndef __GST_PARSE_TYPES_H__ +#define __GST_PARSE_TYPES_H__ + +#include + +/** @brief pipeline element/pad reference */ +typedef struct { + GstElement *element; + gchar *name; + GSList *pads; +} reference_t; + +/** @brief pad-to-pad linkage relation */ +typedef struct { + reference_t src; + reference_t sink; + GstCaps *caps; + gboolean all_pads; +} link_t; + +/** @brief Chain of elements */ +typedef struct { + GSList *elements; + reference_t first; + reference_t last; +} chain_t; + +typedef struct _graph_t graph_t; +/** @brief The pipeline graph */ +struct _graph_t { + chain_t *chain; /* links are supposed to be done now */ + GSList *links; + GError **error; + GstParseContext *ctx; /* may be NULL */ + GstParseFlags flags; +}; + + +/** + * Memory checking. Should probably be done with gsttrace stuff, but that + * doesn't really work. + * This is not safe from reentrance issues, but that doesn't matter as long as + * we lock a mutex before parsing anyway. + * + * FIXME: Disable this for now for the above reasons + */ +#if 0 +#ifdef GST_DEBUG_ENABLED +# define __GST_PARSE_TRACE +#endif +#endif + +#ifdef __GST_PARSE_TRACE +G_GNUC_INTERNAL gchar *__gst_parse_strdup (gchar *org); +G_GNUC_INTERNAL void __gst_parse_strfree (gchar *str); +G_GNUC_INTERNAL link_t *__gst_parse_link_new (void); +G_GNUC_INTERNAL void __gst_parse_link_free (link_t *data); +G_GNUC_INTERNAL chain_t *__gst_parse_chain_new (void); +G_GNUC_INTERNAL void __gst_parse_chain_free (chain_t *data); +# define gst_parse_strdup __gst_parse_strdup +# define gst_parse_strfree __gst_parse_strfree +# define gst_parse_link_new __gst_parse_link_new +# define gst_parse_link_free __gst_parse_link_free +# define gst_parse_chain_new __gst_parse_chain_new +# define gst_parse_chain_free __gst_parse_chain_free +#else /* __GST_PARSE_TRACE */ +# define gst_parse_strdup g_strdup +# define gst_parse_strfree g_free +# define gst_parse_link_new() g_slice_new0 (link_t) +# define gst_parse_link_free(l) g_slice_free (link_t, l) +# define gst_parse_chain_new() g_slice_new0 (chain_t) +# define gst_parse_chain_free(c) g_slice_free (chain_t, c) +#endif /* __GST_PARSE_TRACE */ + +/** @brief GST Parser's internal function imported */ +static inline void +gst_parse_unescape (gchar *str) +{ + gchar *walk; + gboolean in_quotes; + + g_return_if_fail (str != NULL); + + walk = str; + in_quotes = FALSE; + + GST_DEBUG ("unescaping %s", str); + + while (*walk) { + if (*walk == '\\' && !in_quotes) { + walk++; + /* make sure we don't read beyond the end of the string */ + if (*walk == '\0') + break; + } else if (*walk == '"' && (!in_quotes || (in_quotes + && (*(walk - 1) != '\\')))) { + /** don't unescape inside quotes and don't switch + * state with escaped quoted inside quotes */ + in_quotes = !in_quotes; + } + *str = *walk; + str++; + walk++; + } + *str = '\0'; +} + +G_GNUC_INTERNAL GstElement *priv_gst_parse_launch (const gchar * str, + GError ** err, + GstParseContext * ctx, + GstParseFlags flags); + +#endif /* __GST_PARSE_TYPES_H__ */ -- 2.7.4