Add mupdf-curl app

Windows and X11. Allows files to be fetched and displayed
as they are downloaded both with and without linearization, using
hints if available.

1 files changed, 525 insertions, 0 deletions

diff --git a/platform/x11/curl_stream.c b/platform/x11/curl_stream.c
new file mode 100644
index 00000000..3a0de68c
--- /dev/null
+++ b/platform/x11/curl_stream.c
@@ -0,0 +1,525 @@
+/* Simple example fz_stream implementation using curl */
+
+#include "mupdf/fitz.h"
+#include "curl_stream.h"
+
+#define CURL_STATICLIB
+#include <curl/curl.h>
+
+#undef DEBUG_BLOCK_FETCHING
+
+#ifdef DEBUG_BLOCK_FETCHING
+#define DEBUG_MESSAGE(A) do { fz_warn A; } while(0)
+#else
+#define DEBUG_MESSAGE(A) do { } while(0)
+#endif
+
+#define BLOCK_SHIFT 12
+#define BLOCK_SIZE (1<<BLOCK_SHIFT)
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include "pthread.h"
+#include <ctype.h>
+#endif
+
+typedef struct curl_stream_state_s curl_stream_state;
+
+struct curl_stream_state_s
+{
+	fz_context *ctx;
+	CURL *handle;
+	char *filename;
+	int data_arrived;
+	int content_length; /* As returned by curl. -1 for unknown. */
+	int total_length; /* As obtained from the Content-Range header. */
+	int buffer_max;
+	int buffer_fill;
+	unsigned char *buffer;
+	int map_length;
+	unsigned char *map;
+	int fill_point; /* The next file offset we will fetch to */
+	int current_fill_point; /* The current file offset we are fetching to */
+	int complete;
+	int kill_thread;
+	void (*more_data)(void *, int);
+	void *more_data_arg;
+
+#ifdef _WIN32
+	void *thread;
+	DWORD thread_id;
+	HANDLE mutex;
+#else
+	pthread_t thread;
+	pthread_mutex_t mutex;
+#endif
+};
+
+static void fetcher_thread(curl_stream_state *state);
+
+#ifdef _WIN32
+static void
+lock(curl_stream_state *state)
+{
+	WaitForSingleObject(state->mutex, INFINITE);
+}
+
+static void
+unlock(curl_stream_state *state)
+{
+	ReleaseMutex(state->mutex);
+}
+
+static DWORD WINAPI
+win_thread(void *lparam)
+{
+	fetcher_thread((curl_stream_state *)lparam);
+
+	return 0;
+}
+
+#else /* Anything else assumed to be pthreads */
+
+static void
+lock(curl_stream_state *state)
+{
+	pthread_mutex_lock(&state->mutex);
+}
+
+static void
+unlock(curl_stream_state *state)
+{
+	pthread_mutex_unlock(&state->mutex);
+}
+
+
+static void *
+pthread_thread(void *arg)
+{
+	fetcher_thread((curl_stream_state *)arg);
+
+	return NULL;
+}
+#endif
+
+static size_t header_arrived(void *ptr, size_t size, size_t nmemb, void *state_)
+{
+	curl_stream_state *state = (curl_stream_state *)state_;
+
+	if (strncmp(ptr, "Content-Range:", 14) == 0)
+	{
+		char *p = (char *)ptr;
+		int len = nmemb * size;
+		int start, end, total;
+		while (len && !isdigit(*p))
+			p++, len--;
+		start = 0;
+		while (len && isdigit(*p))
+		{
+			start = start*10 + *p-'0';
+			p++, len--;
+		}
+		while (len && !isdigit(*p))
+			p++, len--;
+		end = 0;
+		while (len && isdigit(*p))
+		{
+			end = end*10 + *p-'0';
+			p++, len--;
+		}
+		while (len && !isdigit(*p))
+			p++, len--;
+		total = 0;
+		while (len && isdigit(*p))
+		{
+			total = total*10 + *p-'0';
+			p++, len--;
+		}
+		state->total_length = total;
+	}
+
+	return nmemb * size;
+}
+
+static size_t data_arrived(void *ptr, size_t size, size_t nmemb, void *state_)
+{
+	curl_stream_state *state = (curl_stream_state *)state_;
+	int old_start;
+
+	size *= nmemb;
+
+	if (state->data_arrived == 0)
+	{
+		double d;
+		long response;
+		int len;
+		/* This is the first time data has arrived. If the response
+		 * code is 206, then we can do byte requests, and we will
+		 * known the total_length from having processed the header
+		 * already. */
+		curl_easy_getinfo(state->handle, CURLINFO_RESPONSE_CODE, &response);
+		if (state->total_length && response == 206)
+		{
+			/* We got a range header, and the correct http response
+			 * code. We can assume that byte fetches are accepted
+			 * and we'll run without progressive mode. */
+			state->content_length = len = state->total_length;
+			state->map_length = (len+BLOCK_SIZE-1)>>BLOCK_SHIFT;
+			state->map = fz_malloc_no_throw(state->ctx, (state->map_length+7)>>3);
+			state->buffer = fz_malloc_no_throw(state->ctx, len);
+			state->buffer_max = len;
+			if (state->map == NULL || state->buffer == NULL)
+			{
+				/* FIXME: Crap error handling! */
+				exit(1);
+			}
+			memset(state->map, 0, (state->map_length+7)>>3);
+		}
+		else
+		{
+			/* So we can't use ByteRanges. Do we at least know the
+			 * complete length of the file? */
+			curl_easy_getinfo(state->handle, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
+			state->content_length = len = (int)d;
+			if (len > 0 && response == 200)
+			{
+				/* Yes. We can run as a progressive file */
+				state->buffer = fz_malloc_no_throw(state->ctx, len);
+				state->buffer_max = len;
+				if (state->buffer == NULL)
+				{
+					/* FIXME: Crap error handling! */
+					exit(1);
+				}
+			}
+			else
+			{
+				/* What a crap server. Won't tell us how big
+				 * the file is. We'll have to expand as data
+				 * as arrives. */
+				state->content_length = -1;
+			}
+		}
+		state->data_arrived = 1;
+	}
+	if (state->content_length < 0)
+	{
+		int newsize = state->current_fill_point + size;
+		if (newsize > state->buffer_max)
+		{
+			/* Expand the buffer */
+			int new_max = state->buffer_max * 2;
+			if (new_max == 0)
+				new_max = 4096;
+			state->buffer = fz_resize_array_no_throw(state->ctx, state->buffer, new_max, 1);
+			if (state->buffer == NULL)
+			{
+				/* FIXME: Crap error handling! */
+				exit(1);
+			}
+			state->buffer_max = new_max;
+		}
+	}
+
+	DEBUG_MESSAGE((state->ctx, "data arrived: offset=%d len=%d", state->current_fill_point, size));
+	old_start = state->current_fill_point;
+	memcpy(state->buffer + state->current_fill_point, ptr, size);
+	state->current_fill_point += size;
+	if (state->current_fill_point == state->content_length ||
+		(((state->current_fill_point ^ old_start) & ~(BLOCK_SIZE-1)) != 0))
+	{
+		if (state->map)
+		{
+			old_start >>= BLOCK_SHIFT;
+			state->map[old_start>>3] |= 1<<(old_start & 7);
+		}
+	}
+
+	if (state->more_data)
+		state->more_data(state->more_data_arg, 0);
+
+	return size;
+}
+
+#define HAVE_BLOCK(map, num) \
+	(((map)[(num)>>3] & (1<<((num) & 7))) != 0)
+
+static void
+fetch_chunk(curl_stream_state *state)
+{
+	char text[32];
+	int fill, start, end;
+
+	lock(state);
+
+	if (state->kill_thread)
+	{
+		state->complete = 1;
+		unlock(state);
+		return;
+	}
+
+	fill = state->fill_point;
+	if (state->content_length > 0)
+	{
+		/* Find the next block that we haven't got */
+		int map_length = state->map_length;
+		unsigned char *map = state->map;
+		for ( ; (fill < map_length && HAVE_BLOCK(map, fill)); fill++);
+		if (fill == map_length)
+		{
+			for (fill = 0;
+				(fill < map_length && HAVE_BLOCK(map, fill));
+				fill++);
+			if (fill == map_length)
+			{
+				/* We've got it all! */
+				state->complete = 1;
+				state->kill_thread = 1;
+				unlock(state);
+				if (state->more_data)
+					state->more_data(state->more_data_arg, 1);
+				fz_warn(state->ctx, "Background fetch complete!");
+				return;
+			}
+		}
+		DEBUG_MESSAGE((state->ctx, "block requested was %d, fetching %d", state->fill_point, fill));
+		state->fill_point = fill;
+	}
+
+	unlock(state);
+
+	/* Fetch that block */
+	start = fill * BLOCK_SIZE;
+	end = start + BLOCK_SIZE-1;
+	state->current_fill_point = start;
+	if (state->content_length > 0 && start >= state->content_length)
+		state->complete = 1;
+	if (state->content_length > 0 && end >= state->content_length)
+		end = state->content_length-1;
+	snprintf(text, 32, "%d-%d", start, end);
+	curl_easy_setopt(state->handle, CURLOPT_RANGE, text);
+	curl_easy_perform(state->handle);
+}
+
+static void
+fetcher_thread(curl_stream_state *state)
+{
+	while (!state->complete)
+		fetch_chunk(state);
+}
+
+static int
+stream_read(fz_stream *stream, unsigned char *buf, int len)
+{
+	curl_stream_state *state = (curl_stream_state *)stream->state;
+	int len_read = 0;
+	int read_point = stream->pos;
+	int block = read_point>>BLOCK_SHIFT;
+	int left_over = (-read_point) & (BLOCK_SIZE-1);
+
+	if (state->content_length == 0)
+		fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "read of a block we don't have (A) (offset=%d)", read_point);
+
+	if (state->map == NULL)
+	{
+		/* We are doing a simple linear fetch as we don't know the
+		 * content length. */
+		if (read_point + len > state->current_fill_point)
+		{
+			stream->rp = stream->wp = stream->bp;
+			fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "read of a block we don't have (B) (offset=%d)", read_point);
+		}
+		memcpy(buf, state->buffer + read_point, len);
+		return len;
+	}
+
+	if (read_point + len > state->content_length)
+		len = state->content_length - read_point;
+	if (left_over > len)
+		left_over = len;
+
+	if (left_over)
+	{
+		/* We are starting midway through a block */
+		if (!HAVE_BLOCK(state->map, block))
+		{
+			lock(state);
+			state->fill_point = block;
+			unlock(state);
+			stream->rp = stream->wp = stream->bp;
+			fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "read of a block we don't have (C) (offset=%d)", read_point);
+		}
+		block++;
+		if (left_over > len)
+			left_over = len;
+		memcpy(buf, state->buffer + read_point, left_over);
+		buf += left_over;
+		read_point += left_over;
+		len -= left_over;
+		len_read += left_over;
+	}
+
+	/* Copy any complete blocks */
+	while (len > BLOCK_SIZE)
+	{
+		if (!HAVE_BLOCK(state->map, block))
+		{
+			lock(state);
+			state->fill_point = block;
+			unlock(state);
+			stream->rp = stream->wp = stream->bp;
+			fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "read of a block we don't have (D) (offset=%d)", read_point);
+		}
+		block++;
+		memcpy(buf, state->buffer + read_point, BLOCK_SIZE);
+		buf += BLOCK_SIZE;
+		read_point += BLOCK_SIZE;
+		len -= BLOCK_SIZE;
+		len_read += BLOCK_SIZE;
+	}
+
+	/* Copy any trailing bytes */
+	if (len > 0)
+	{
+		if (!HAVE_BLOCK(state->map, block))
+		{
+			lock(state);
+			state->fill_point = block;
+			unlock(state);
+			stream->rp = stream->wp = stream->bp;
+			fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "read of a block we don't have (E) (offset=%d)", read_point);
+		}
+		memcpy(buf, state->buffer + read_point, len);
+		len_read += len;
+	}
+
+	return len_read;
+}
+
+static void
+stream_close(fz_context *ctx, void *state_)
+{
+	curl_stream_state *state = (curl_stream_state *)state_;
+
+	if (!state || state->kill_thread)
+		return;
+
+	lock(state);
+	state->kill_thread = 1;
+	unlock(state);
+
+#ifdef _WIN32
+	WaitForSingleObject(state->thread, INFINITE);
+	CloseHandle(state->thread);
+	CloseHandle(state->mutex);
+#else
+	pthread_join(state->thread, NULL);
+	pthread_mutex_destroy(&state->mutex);
+#endif
+
+	fz_free(state->ctx, state->buffer);
+	fz_free(state->ctx, state->map);
+	fz_free(state->ctx, state);
+}
+
+static fz_stream hack_stream;
+static curl_stream_state hack;
+static int hack_pos;
+
+static void
+stream_seek(fz_stream *stream, int offset, int whence)
+{
+	curl_stream_state *state = (curl_stream_state *)stream->state;
+
+	switch(whence)
+	{
+	case SEEK_CUR:
+		offset += stream->pos;
+		break;
+	case SEEK_END:
+		offset += state->content_length;
+		break;
+	default:
+	case SEEK_SET:
+		break;
+	}
+	if (offset < 0)
+		offset = 0;
+	else if (state->content_length > 0 && offset > state->content_length)
+		offset = state->content_length;
+	stream->wp = stream->rp = stream->bp;
+	stream->pos = offset;
+	hack = *state;
+	hack_pos = offset;
+	hack_stream = *stream;
+}
+
+static int
+stream_meta(fz_stream *stream, int key, int size, void *ptr)
+{
+	curl_stream_state *state = (curl_stream_state *)stream->state;
+
+	switch(key)
+	{
+	case FZ_STREAM_META_LENGTH:
+		if (!state->data_arrived)
+			fz_throw(stream->ctx, FZ_ERROR_TRYLATER, "still awaiting file length");
+		return state->content_length;
+	case FZ_STREAM_META_PROGRESSIVE:
+		return 1;
+	}
+	return -1;
+}
+
+fz_stream *fz_stream_from_curl(fz_context *ctx, char *filename, void (*more_data)(void *,int), void *more_data_arg)
+{
+	CURLcode ret;
+	CURL *handle;
+	curl_stream_state *state = fz_malloc_struct(ctx, curl_stream_state);
+	fz_stream *stream;
+
+	ret = curl_global_init(CURL_GLOBAL_ALL);
+	if (ret != 0)
+		fz_throw(ctx, FZ_ERROR_GENERIC, "curl init failed (code %d)", ret);
+
+	state->ctx = ctx;
+	state->handle = handle = curl_easy_init();
+	state->more_data = more_data;
+	state->more_data_arg = more_data_arg;
+
+	curl_easy_setopt(handle, CURLOPT_URL, filename);
+
+	curl_easy_setopt(handle, CURLOPT_NOPROGRESS, 1);
+
+	curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, data_arrived);
+
+	curl_easy_setopt(handle, CURLOPT_WRITEDATA, state);
+
+	curl_easy_setopt(handle, CURLOPT_WRITEHEADER, state);
+
+	curl_easy_setopt(handle, CURLOPT_HEADERFUNCTION, header_arrived);
+
+#ifdef _WIN32
+	state->mutex = CreateMutex(NULL, FALSE, NULL);
+	if (state->mutex == NULL)
+		fz_throw(ctx, FZ_ERROR_GENERIC, "mutex creation failed");
+
+	state->thread = CreateThread(NULL, 0, win_thread, state, 0, &state->thread_id);
+	if (state->thread == NULL)
+		fz_throw(ctx, FZ_ERROR_GENERIC, "thread creation failed");
+#else
+	if (pthread_mutex_init(&state->mutex, NULL))
+		fz_throw(ctx, FZ_ERROR_GENERIC, "mutex creation failed");
+
+	if (pthread_create(&state->thread, NULL, pthread_thread, state))
+		fz_throw(ctx, FZ_ERROR_GENERIC, "thread creation failed");
+
+#endif
+
+	stream = fz_new_stream(ctx, state, stream_read, stream_close);
+	stream->seek = stream_seek;
+	stream->meta = stream_meta;
+	return stream;
+}