Throw exceptions for read errors.

12 files changed, 60 insertions, 102 deletions

diff --git a/apps/pdfdraw.c b/apps/pdfdraw.c
index 6d43dc01..ff9f72a3 100644
--- a/apps/pdfdraw.c
+++ b/apps/pdfdraw.c
@@ -365,7 +365,7 @@ int main(int argc, char **argv)
 	ctx = fz_new_context(&fz_alloc_default);
 	if (ctx == NULL)
 	{
-		fprintf(stderr, "Failed to init context\n");
+		fprintf(stderr, "cannot init context\n");
 		exit(1);
 	}
 
diff --git a/apps/win_main.c b/apps/win_main.c
index 3e293957..45880e12 100644
--- a/apps/win_main.c
+++ b/apps/win_main.c
@@ -861,7 +861,7 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShow
 	ctx = fz_new_context(&fz_alloc_default);
 	if (ctx == NULL)
 	{
-		fprintf(stderr, "Failed to init context");
+		fprintf(stderr, "cannot init context");
 		exit(1);
 	}
 	pdfapp_init(ctx, &gapp);
diff --git a/fitz/filt_basic.c b/fitz/filt_basic.c
index 0842ec36..1ab70f7f 100644
--- a/fitz/filt_basic.c
+++ b/fitz/filt_basic.c
@@ -22,8 +22,6 @@ read_null(fz_stream *stm, unsigned char *buf, int len)
 	struct null_filter *state = stm->state;
 	int amount = MIN(len, state->remain);
 	int n = fz_read(state->chain, buf, amount);
-	if (n < 0)
-		return fz_error_note(n, "read error in null filter");
 	state->remain -= n;
 	return n;
 }
@@ -33,7 +31,6 @@ close_null(fz_stream *stm)
 {
 	struct null_filter *state = stm->state;
 	fz_stream *chain = state->chain;
-
 	fz_free(stm->ctx, state);
 	fz_close(chain);
 }
@@ -127,7 +124,7 @@ read_ahxd(fz_stream *stm, unsigned char *buf, int len)
 		}
 		else if (!iswhite(c))
 		{
-			return fz_error_make("bad data in ahxd: '%c'", c);
+			fz_throw(stm->ctx, "bad data in ahxd: '%c'", c);
 		}
 	}
 
@@ -139,7 +136,6 @@ close_ahxd(fz_stream *stm)
 {
 	fz_ahxd *state = stm->state;
 	fz_stream *chain = state->chain;
-
 	fz_free(stm->ctx, state);
 	fz_close(chain);
 }
@@ -233,7 +229,7 @@ read_a85d(fz_stream *stm, unsigned char *buf, int len)
 			case 0:
 				break;
 			case 1:
-				return fz_error_make("partial final byte in a85d");
+				fz_throw(stm->ctx, "partial final byte in a85d");
 			case 2:
 				word = word * (85 * 85 * 85) + 0xffffff;
 				state->bp[0] = word >> 24;
@@ -261,7 +257,7 @@ read_a85d(fz_stream *stm, unsigned char *buf, int len)
 
 		else if (!iswhite(c))
 		{
-			return fz_error_make("bad data in a85d: '%c'", c);
+			fz_throw(stm->ctx, "bad data in a85d: '%c'", c);
 		}
 
 		while (state->rp < state->wp && p < ep)
@@ -330,7 +326,7 @@ read_rld(fz_stream *stm, unsigned char *buf, int len)
 				state->n = 257 - state->run;
 				state->c = fz_read_byte(state->chain);
 				if (state->c < 0)
-					return fz_error_make("premature end of data in run length decode");
+					fz_throw(stm->ctx, "premature end of data in run length decode");
 			}
 		}
 
@@ -340,7 +336,7 @@ read_rld(fz_stream *stm, unsigned char *buf, int len)
 			{
 				int c = fz_read_byte(state->chain);
 				if (c < 0)
-					return fz_error_make("premature end of data in run length decode");
+					fz_throw(stm->ctx, "premature end of data in run length decode");
 				*p++ = c;
 				state->n--;
 			}
@@ -398,14 +394,8 @@ static int
 read_arc4(fz_stream *stm, unsigned char *buf, int len)
 {
 	fz_arc4c *state = stm->state;
-	int n;
-
-	n = fz_read(state->chain, buf, len);
-	if (n < 0)
-		return fz_error_note(n, "read error in arc4 filter");
-
+	int n = fz_read(state->chain, buf, len);
 	fz_arc4_encrypt(&state->arc4, buf, buf, n);
-
 	return n;
 }
 
@@ -456,7 +446,7 @@ read_aesd(fz_stream *stm, unsigned char *buf, int len)
 	{
 		int c = fz_read_byte(state->chain);
 		if (c < 0)
-			return fz_error_make("premature end in aes filter");
+			fz_throw(stm->ctx, "premature end in aes filter");
 		state->iv[state->ivcount++] = c;
 	}
 
@@ -466,12 +456,10 @@ read_aesd(fz_stream *stm, unsigned char *buf, int len)
 	while (p < ep)
 	{
 		int n = fz_read(state->chain, state->bp, 16);
-		if (n < 0)
-			return fz_error_note(n, "read error in aes filter");
-		else if (n == 0)
+		if (n == 0)
 			return p - buf;
 		else if (n < 16)
-			return fz_error_make("partial block in aes filter");
+			fz_throw(stm->ctx, "partial block in aes filter");
 
 		aes_crypt_cbc(&state->aes, AES_DECRYPT, 16, state->iv, state->bp, state->bp);
 		state->rp = state->bp;
@@ -482,7 +470,7 @@ read_aesd(fz_stream *stm, unsigned char *buf, int len)
 		{
 			int pad = state->bp[15];
 			if (pad < 1 || pad > 16)
-				return fz_error_make("aes padding out of range: %d", pad);
+				fz_throw(stm->ctx, "aes padding out of range: %d", pad);
 			state->wp -= pad;
 		}
 
diff --git a/fitz/filt_dctd.c b/fitz/filt_dctd.c
index fb0e77e7..355cca91 100644
--- a/fitz/filt_dctd.c
+++ b/fitz/filt_dctd.c
@@ -87,7 +87,7 @@ read_dctd(fz_stream *stm, unsigned char *buf, int len)
 	{
 		if (cinfo->src)
 			state->chain->rp = state->chain->wp - cinfo->src->bytes_in_buffer;
-		return fz_error_make("jpeg error: %s", state->msg);
+		fz_throw(stm->ctx, "jpeg error: %s", state->msg);
 	}
 
 	if (!state->init)
diff --git a/fitz/filt_faxd.c b/fitz/filt_faxd.c
index 14a71a87..f94a2cd6 100644
--- a/fitz/filt_faxd.c
+++ b/fitz/filt_faxd.c
@@ -265,6 +265,7 @@ enum
 
 struct fz_faxd_s
 {
+	fz_context *ctx;
 	fz_stream *chain;
 
 	int k;
@@ -331,8 +332,8 @@ get_code(fz_faxd *fax, const cfd_node *table, int initialbits)
 }
 
 /* decode one 1d code */
-static fz_error
-dec1d(fz_faxd *fax)
+static void
+dec1d(fz_context *ctx, fz_faxd *fax)
 {
 	int code;
 
@@ -345,13 +346,13 @@ dec1d(fz_faxd *fax)
 		code = get_code(fax, cf_white_decode, cfd_white_initial_bits);
 
 	if (code == UNCOMPRESSED)
-		return fz_error_make("uncompressed data in faxd");
+		fz_throw(ctx, "uncompressed data in faxd");
 
 	if (code < 0)
-		return fz_error_make("negative code in 1d faxd");
+		fz_throw(ctx, "negative code in 1d faxd");
 
 	if (fax->a + code > fax->columns)
-		return fz_error_make("overflow in 1d faxd");
+		fz_throw(ctx, "overflow in 1d faxd");
 
 	if (fax->c)
 		setbits(fax->dst, fax->a, fax->a + code);
@@ -365,13 +366,11 @@ dec1d(fz_faxd *fax)
 	}
 	else
 		fax->stage = STATE_MAKEUP;
-
-	return fz_okay;
 }
 
 /* decode one 2d code */
-static fz_error
-dec2d(fz_faxd *fax)
+static void
+dec2d(fz_context *ctx, fz_faxd *fax)
 {
 	int code, b1, b2;
 
@@ -386,13 +385,13 @@ dec2d(fz_faxd *fax)
 			code = get_code(fax, cf_white_decode, cfd_white_initial_bits);
 
 		if (code == UNCOMPRESSED)
-			return fz_error_make("uncompressed data in faxd");
+			fz_throw(ctx, "uncompressed data in faxd");
 
 		if (code < 0)
-			return fz_error_make("negative code in 2d faxd");
+			fz_throw(ctx, "negative code in 2d faxd");
 
 		if (fax->a + code > fax->columns)
-			return fz_error_make("overflow in 2d faxd");
+			fz_throw(ctx, "overflow in 2d faxd");
 
 		if (fax->c)
 			setbits(fax->dst, fax->a, fax->a + code);
@@ -408,7 +407,7 @@ dec2d(fz_faxd *fax)
 				fax->stage = STATE_NORMAL;
 		}
 
-		return fz_okay;
+		return;
 	}
 
 	code = get_code(fax, cf_2d_decode, cfd_2d_initial_bits);
@@ -485,16 +484,14 @@ dec2d(fz_faxd *fax)
 		break;
 
 	case UNCOMPRESSED:
-		return fz_error_make("uncompressed data in faxd");
+		fz_throw(ctx, "uncompressed data in faxd");
 
 	case ERROR:
-		return fz_error_make("invalid code in 2d faxd");
+		fz_throw(ctx, "invalid code in 2d faxd");
 
 	default:
-		return fz_error_make("invalid code in 2d faxd (%d)", code);
+		fz_throw(ctx, "invalid code in 2d faxd (%d)", code);
 	}
-
-	return 0;
 }
 
 static int
@@ -504,7 +501,6 @@ read_faxd(fz_stream *stm, unsigned char *buf, int len)
 	unsigned char *p = buf;
 	unsigned char *ep = buf + len;
 	unsigned char *tmp;
-	fz_error error;
 
 	if (fax->stage == STATE_DONE)
 		return 0;
@@ -558,16 +554,12 @@ loop:
 	else if (fax->dim == 1)
 	{
 		fax->eolc = 0;
-		error = dec1d(fax);
-		if (error)
-			return fz_error_note(error, "cannot decode 1d code");
+		dec1d(stm->ctx, fax);
 	}
 	else if (fax->dim == 2)
 	{
 		fax->eolc = 0;
-		error = dec2d(fax);
-		if (error)
-			return fz_error_note(error, "cannot decode 2d code");
+		dec2d(stm->ctx, fax);
 	}
 
 	/* no eol check after makeup codes nor in the middle of an H code */
diff --git a/fitz/filt_flate.c b/fitz/filt_flate.c
index 11100c94..d7077bc8 100644
--- a/fitz/filt_flate.c
+++ b/fitz/filt_flate.c
@@ -59,7 +59,7 @@ read_flated(fz_stream *stm, unsigned char *outbuf, int outlen)
 		}
 		else if (code != Z_OK)
 		{
-			return fz_error_make("zlib error: %s", zp->msg);
+			fz_throw(stm->ctx, "zlib error: %s", zp->msg);
 		}
 	}
 
diff --git a/fitz/filt_jbig2d.c b/fitz/filt_jbig2d.c
index 18aa0a22..e2ae4d93 100644
--- a/fitz/filt_jbig2d.c
+++ b/fitz/filt_jbig2d.c
@@ -56,8 +56,6 @@ read_jbig2d(fz_stream *stm, unsigned char *buf, int len)
 		while (1)
 		{
 			n = fz_read(state->chain, tmp, sizeof tmp);
-			if (n < 0)
-				return fz_error_note(n, "read error in jbig2 filter");
 			if (n == 0)
 				break;
 			jbig2_data_in(state->ctx, tmp, n);
@@ -67,7 +65,7 @@ read_jbig2d(fz_stream *stm, unsigned char *buf, int len)
 
 		state->page = jbig2_page_out(state->ctx);
 		if (!state->page)
-			return fz_error_make("jbig2_page_out failed");
+			fz_throw(stm->ctx, "jbig2_page_out failed");
 	}
 
 	s = state->page->data;
diff --git a/fitz/filt_predict.c b/fitz/filt_predict.c
index ed0d6d98..d640373e 100644
--- a/fitz/filt_predict.c
+++ b/fitz/filt_predict.c
@@ -153,8 +153,6 @@ read_predict(fz_stream *stm, unsigned char *buf, int len)
 	while (p < ep)
 	{
 		n = fz_read(state->chain, state->in, state->stride + ispng);
-		if (n < 0)
-			return fz_error_note(n, "read error in prediction filter");
 		if (n == 0)
 			return p - buf;
 
diff --git a/fitz/res_font.c b/fitz/res_font.c
index 4b30d424..3fea732a 100644
--- a/fitz/res_font.c
+++ b/fitz/res_font.c
@@ -154,7 +154,7 @@ char *ft_error_string(int err)
 	return "Unknown error";
 }
 
-static fz_error
+static void
 fz_init_freetype(fz_context *ctx)
 {
 	int fterr;
@@ -164,12 +164,12 @@ fz_init_freetype(fz_context *ctx)
 	if (fct->ftlib)
 	{
 		fct->ftlib_refs++;
-		return fz_okay;
+		return;
 	}
 
 	fterr = FT_Init_FreeType(&fct->ftlib);
 	if (fterr)
-		return fz_error_make("cannot init freetype: %s", ft_error_string(fterr));
+		fz_throw(ctx, "cannot init freetype: %s", ft_error_string(fterr));
 
 	FT_Library_Version(fct->ftlib, &maj, &min, &pat);
 	if (maj == 2 && min == 1 && pat < 7)
@@ -177,11 +177,10 @@ fz_init_freetype(fz_context *ctx)
 		fterr = FT_Done_FreeType(fct->ftlib);
 		if (fterr)
 			fz_warn(ctx, "freetype finalizing: %s", ft_error_string(fterr));
-		return fz_error_make("freetype version too old: %d.%d.%d", maj, min, pat);
+		fz_throw(ctx, "freetype version too old: %d.%d.%d", maj, min, pat);
 	}
 
 	fct->ftlib_refs++;
-	return fz_okay;
 }
 
 static void
@@ -203,13 +202,10 @@ fz_font *
 fz_new_font_from_file(fz_context *ctx, char *path, int index)
 {
 	FT_Face face;
-	fz_error error;
 	fz_font *font;
 	int fterr;
 
-	error = fz_init_freetype(ctx);
-	if (error)
-		fz_throw(ctx, "cannot init freetype library");
+	fz_init_freetype(ctx);
 
 	fterr = FT_New_Face(ctx->font->ftlib, path, index, &face);
 	if (fterr)
@@ -229,13 +225,10 @@ fz_font *
 fz_new_font_from_memory(fz_context *ctx, unsigned char *data, int len, int index)
 {
 	FT_Face face;
-	fz_error error;
 	fz_font *font;
 	int fterr;
 
-	error = fz_init_freetype(ctx);
-	if (error)
-		fz_throw(ctx, "cannot init freetype library");
+	fz_init_freetype(ctx);
 
 	fterr = FT_New_Memory_Face(ctx->font->ftlib, data, len, index, &face);
 	if (fterr)
diff --git a/fitz/stm_open.c b/fitz/stm_open.c
index aa99451b..9f657f27 100644
--- a/fitz/stm_open.c
+++ b/fitz/stm_open.c
@@ -58,7 +58,7 @@ static int read_file(fz_stream *stm, unsigned char *buf, int len)
 {
 	int n = read(*(int*)stm->state, buf, len);
 	if (n < 0)
-		return fz_error_make("read error: %s", strerror(errno));
+		fz_throw(stm->ctx, "read error: %s", strerror(errno));
 	return n;
 }
 
@@ -66,7 +66,7 @@ static void seek_file(fz_stream *stm, int offset, int whence)
 {
 	int n = lseek(*(int*)stm->state, offset, whence);
 	if (n < 0)
-		fz_warn(stm->ctx, "cannot lseek: %s", strerror(errno));
+		fz_throw(stm->ctx, "cannot lseek: %s", strerror(errno));
 	stm->pos = n;
 	stm->rp = stm->bp;
 	stm->wp = stm->bp;
@@ -100,7 +100,7 @@ fz_open_file(fz_context *ctx, const char *name)
 {
 	int fd = open(name, O_BINARY | O_RDONLY, 0);
 	if (fd == -1)
-		fz_throw(ctx, "Failed to open %s", name);
+		fz_throw(ctx, "cannot open %s", name);
 	return fz_open_fd(ctx, fd);
 }
 
diff --git a/fitz/stm_read.c b/fitz/stm_read.c
index 5622a24f..9f9fc302 100644
--- a/fitz/stm_read.c
+++ b/fitz/stm_read.c
@@ -20,12 +20,7 @@ fz_read(fz_stream *stm, unsigned char *buf, int len)
 	if (len - count < stm->ep - stm->bp)
 	{
 		n = stm->read(stm, stm->bp, stm->ep - stm->bp);
-		if (n < 0)
-		{
-			stm->error = 1;
-			return fz_error_note(n, "read error");
-		}
-		else if (n == 0)
+		if (n == 0)
 		{
 			stm->eof = 1;
 		}
@@ -47,12 +42,7 @@ fz_read(fz_stream *stm, unsigned char *buf, int len)
 	else
 	{
 		n = stm->read(stm, buf + count, len - count);
-		if (n < 0)
-		{
-			stm->error = 1;
-			return fz_error_note(n, "read error");
-		}
-		else if (n == 0)
+		if (n == 0)
 		{
 			stm->eof = 1;
 		}
@@ -76,21 +66,24 @@ fz_fill_buffer(fz_stream *stm)
 	if (stm->error || stm->eof)
 		return;
 
-	n = stm->read(stm, stm->bp, stm->ep - stm->bp);
-	if (n < 0)
+	fz_try(stm->ctx)
 	{
-		stm->error = 1;
-		fz_error_handle(n, "read error; treating as end of file");
-	}
-	else if (n == 0)
-	{
-		stm->eof = 1;
+		n = stm->read(stm, stm->bp, stm->ep - stm->bp);
+		if (n == 0)
+		{
+			stm->eof = 1;
+		}
+		else if (n > 0)
+		{
+			stm->rp = stm->bp;
+			stm->wp = stm->bp + n;
+			stm->pos += n;
+		}
 	}
-	else if (n > 0)
+	fz_catch(stm->ctx)
 	{
-		stm->rp = stm->bp;
-		stm->wp = stm->bp + n;
-		stm->pos += n;
+		fz_warn(stm->ctx, "read error; treating as end of file");
+		stm->error = 1;
 	}
 }
 
@@ -118,11 +111,6 @@ fz_read_all(fz_stream *stm, int initial)
 		}
 
 		n = fz_read(stm, buf->data + buf->len, buf->cap - buf->len);
-		if (n < 0)
-		{
-			fz_drop_buffer(ctx, buf);
-			fz_throw(ctx, "read error");
-		}
 		if (n == 0)
 			break;
 
diff --git a/pdf/pdf_xref.c b/pdf/pdf_xref.c
index b447dde6..65c695f6 100644
--- a/pdf/pdf_xref.c
+++ b/pdf/pdf_xref.c
@@ -424,7 +424,7 @@ pdf_read_xref_sections(pdf_xref *xref, int ofs, char *buf, int cap)
 	fz_catch(ctx)
 	{
 		fz_drop_obj(trailer);
-		fz_throw(ctx, "Failed to read xref at offset %d", ofs);
+		fz_throw(ctx, "cannot read xref at offset %d", ofs);
 	}
 
 	fz_drop_obj(trailer);
@@ -675,6 +675,7 @@ pdf_open_xref_with_stream(fz_stream *file, char *password)
 			fz_drop_obj(xref->trailer);
 			xref->trailer = NULL;
 		}
+		fz_warn(xref->ctx, "trying to repair broken xref");
 		pdf_repair_xref(xref, xref->scratch, sizeof xref->scratch);
 		repaired = 1;
 	}