API redesign 5/10: pe_unit_ctx: protect members against direct modification.

4 files changed, 44 insertions, 17 deletions

diff --git a/include/perk/perk.h b/include/perk/perk.h
index f19e596..0b84349 100644
--- a/include/perk/perk.h
+++ b/include/perk/perk.h
@@ -135,10 +135,12 @@ struct pe_driver_ctx {
 };
 
 struct pe_unit_ctx {
-	const char *			path;
-	struct pe_raw_image		map;
-	struct pe_image_meta *		meta;
-	struct pe_common_ctx		cctx;
+	const char * const *		path;
+	const struct pe_raw_image *	map;
+	const struct pe_image_meta *	meta;
+	const struct pe_common_ctx *	cctx;
+	int				status;
+	int				nerrors;
 };
 
 /* driver api */
diff --git a/src/driver/pe_unit_ctx.c b/src/driver/pe_unit_ctx.c
index b86719c..df5409b 100644
--- a/src/driver/pe_unit_ctx.c
+++ b/src/driver/pe_unit_ctx.c
@@ -1,10 +1,13 @@
 #include <stdint.h>
+#include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
+
 #include <perk/perk.h>
+#include "perk_impl.h"
 
-static int pe_free_unit_ctx_impl(struct pe_unit_ctx * ctx, int status)
+static int pe_free_unit_ctx_impl(struct pe_unit_ctx_impl * ctx, int status)
 {
 	if (ctx) {
 		pe_free_image_meta(ctx->meta);
@@ -20,7 +23,7 @@ int pe_get_unit_ctx(
 	const char *		path,
 	struct pe_unit_ctx **	pctx)
 {
-	struct pe_unit_ctx *	ctx;
+	struct pe_unit_ctx_impl *	ctx;
 	int			prot;
 
 	if (!dctx || !(ctx = calloc(sizeof(*ctx),1)))
@@ -39,14 +42,26 @@ int pe_get_unit_ctx(
 	memcpy(&ctx->cctx,dctx->cctx,
 		sizeof(ctx->cctx));
 
-	ctx->path	= path;
+	ctx->path	= ctx->path;
 	ctx->cctx.prot	= prot;
 
-	*pctx = ctx;
+	ctx->uctx.path	= &ctx->path;
+	ctx->uctx.map	= &ctx->map;
+	ctx->uctx.meta	= ctx->meta;
+	ctx->uctx.cctx	= &ctx->cctx;
+
+	*pctx = &ctx->uctx;
 	return 0;
 }
 
 void pe_free_unit_ctx(struct pe_unit_ctx * ctx)
 {
-	pe_free_unit_ctx_impl(ctx,0);
+	struct pe_unit_ctx_impl *	ictx;
+	uintptr_t			addr;
+
+	if (ctx) {
+		addr = (uintptr_t)ctx - offsetof(struct pe_unit_ctx_impl,uctx);
+		ictx = (struct pe_unit_ctx_impl *)addr;
+		pe_free_unit_ctx_impl(ictx,0);
+	}
 }
diff --git a/src/internal/perk_impl.h b/src/internal/perk_impl.h
index dd8ff4d..77a64ae 100644
--- a/src/internal/perk_impl.h
+++ b/src/internal/perk_impl.h
@@ -13,4 +13,12 @@ struct pe_driver_ctx_impl {
 	struct pe_driver_ctx	ctx;
 };
 
+struct pe_unit_ctx_impl {
+	const char *		path;
+	struct pe_raw_image	map;
+	struct pe_image_meta *	meta;
+	struct pe_common_ctx	cctx;
+	struct pe_unit_ctx	uctx;
+};
+
 #endif
diff --git a/src/perk.c b/src/perk.c
index c057fc2..85a601f 100644
--- a/src/perk.c
+++ b/src/perk.c
@@ -27,8 +27,8 @@ static ssize_t perk_paragraph_break(struct pe_unit_ctx * uctx, int * fpara)
 	if (*fpara) {
 		*fpara = 0;
 
-		if (uctx->cctx.fdout >= 0)
-			return write(uctx->cctx.fdout,"\n",1);
+		if (uctx->cctx->fdout >= 0)
+			return write(uctx->cctx->fdout,"\n",1);
 		else
 			return fputc('\n',stdout);
 	} else
@@ -38,24 +38,26 @@ static ssize_t perk_paragraph_break(struct pe_unit_ctx * uctx, int * fpara)
 static void perk_perform_unit_actions(struct pe_unit_ctx * uctx)
 {
 	int      fpara = 0;
-	uint64_t flags = uctx->cctx.fmtflags;
+	uint64_t flags = uctx->cctx->fmtflags;
 
 	if (flags & PERK_OUTPUT_EXPORT_SYMS) {
-		uctx->cctx.status = pe_output_export_symbols(uctx->meta,&uctx->cctx,0);
+		uctx->status = pe_output_export_symbols(uctx->meta,uctx->cctx,0);
+		uctx->nerrors += !!uctx->status;
 		fpara += uctx->meta->summary.num_of_export_syms;
 	}
 
 	if ((flags & PERK_OUTPUT_IMPORT_LIBS) || (flags & PERK_OUTPUT_IMPORT_SYMS)) {
 		perk_paragraph_break(uctx,&fpara);
-		uctx->cctx.status = pe_output_import_libraries(uctx->meta,&uctx->cctx,0);
+		uctx->status = pe_output_import_libraries(uctx->meta,uctx->cctx,0);
+		uctx->nerrors += !!uctx->status;
 		fpara += (uctx->meta->summary.num_of_implibs > 0);
 	}
 }
 
-static int perk_exit(struct pe_driver_ctx * dctx, int status)
+static int perk_exit(struct pe_driver_ctx * dctx, int nerrors)
 {
 	pe_free_driver_ctx(dctx);
-	return (status < 0) ? 2 : status;
+	return nerrors ? 2 : 0;
 }
 
 static int perk_main(int argc, const char ** argv, const char ** envp)
@@ -75,7 +77,7 @@ static int perk_main(int argc, const char ** argv, const char ** envp)
 	for (unit=dctx->units; *unit; unit++) {
 		if (!(pe_get_unit_ctx(dctx,*unit,&uctx))) {
 			perk_perform_unit_actions(uctx);
-			ret = uctx->cctx.status ? uctx->cctx.status : ret;
+			ret += uctx->nerrors;
 			pe_free_unit_ctx(uctx);
 		}
 	}