From a4e58de14678503fd773e7920359028de77711f9 Mon Sep 17 00:00:00 2001
From: Akihiko Odaki <akihiko.odaki@daynix.com>
Date: Thu, 7 Mar 2024 19:20:45 +0900
Subject: [PATCH] contrib/elf2dmp: Assume error by default

A common construct in contrib/elf2dmp is to set "err" flag and goto
in error paths. In such a construct, there is only one successful path
while there are several error paths, so it will be more simpler to
initialize "err" flag set, and clear it in the successful path.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Viktor Prutyanov <viktor.prutyanov@phystech.edu>
Message-id: 20240307-elf2dmp-v4-2-4f324ad4d99d@daynix.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 contrib/elf2dmp/download.c |  4 +---
 contrib/elf2dmp/main.c     | 15 +++------------
 2 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/contrib/elf2dmp/download.c b/contrib/elf2dmp/download.c
index bd7650a7a2..902dc04ffa 100644
--- a/contrib/elf2dmp/download.c
+++ b/contrib/elf2dmp/download.c
@@ -11,7 +11,7 @@
 
 int download_url(const char *name, const char *url)
 {
-    int err = 0;
+    int err = 1;
     FILE *file;
     CURL *curl = curl_easy_init();
 
@@ -21,7 +21,6 @@ int download_url(const char *name, const char *url)
 
     file = fopen(name, "wb");
     if (!file) {
-        err = 1;
         goto out_curl;
     }
 
@@ -33,7 +32,6 @@ int download_url(const char *name, const char *url)
             || curl_easy_perform(curl) != CURLE_OK) {
         unlink(name);
         fclose(file);
-        err = 1;
     } else {
         err = fclose(file);
     }
diff --git a/contrib/elf2dmp/main.c b/contrib/elf2dmp/main.c
index cbc38a7c10..9b278f392e 100644
--- a/contrib/elf2dmp/main.c
+++ b/contrib/elf2dmp/main.c
@@ -511,7 +511,7 @@ static void pe_get_pdb_symstore_hash(OMFSignatureRSDS *rsds, char *hash)
 
 int main(int argc, char *argv[])
 {
-    int err = 0;
+    int err = 1;
     QEMU_Elf qemu_elf;
     struct pa_space ps;
     struct va_space vs;
@@ -542,7 +542,6 @@ int main(int argc, char *argv[])
 
     if (pa_space_create(&ps, &qemu_elf)) {
         eprintf("Failed to initialize physical address space\n");
-        err = 1;
         goto out_elf;
     }
 
@@ -552,7 +551,6 @@ int main(int argc, char *argv[])
     va_space_create(&vs, &ps, state->cr[3]);
     if (fix_dtb(&vs, &qemu_elf)) {
         eprintf("Failed to find paging base\n");
-        err = 1;
         goto out_elf;
     }
 
@@ -561,7 +559,6 @@ int main(int argc, char *argv[])
     if (va_space_rw(&vs, state->idt.base,
                 &first_idt_desc, sizeof(first_idt_desc), 0)) {
         eprintf("Failed to get CPU #0 IDT[0]\n");
-        err = 1;
         goto out_ps;
     }
     printf("CPU #0 IDT[0] -> 0x%016"PRIx64"\n", idt_desc_addr(first_idt_desc));
@@ -586,7 +583,6 @@ int main(int argc, char *argv[])
 
     if (!kernel_found) {
         eprintf("Failed to find NT kernel image\n");
-        err = 1;
         goto out_ps;
     }
 
@@ -600,45 +596,40 @@ int main(int argc, char *argv[])
 
     if (download_url(PDB_NAME, pdb_url)) {
         eprintf("Failed to download PDB file\n");
-        err = 1;
         goto out_ps;
     }
 
     if (pdb_init_from_file(PDB_NAME, &pdb)) {
         eprintf("Failed to initialize PDB reader\n");
-        err = 1;
         goto out_pdb_file;
     }
 
     if (!SYM_RESOLVE(KernBase, &pdb, KdDebuggerDataBlock) ||
             !SYM_RESOLVE(KernBase, &pdb, KdVersionBlock)) {
-        err = 1;
         goto out_pdb;
     }
 
     kdbg = get_kdbg(KernBase, &pdb, &vs, KdDebuggerDataBlock);
     if (!kdbg) {
-        err = 1;
         goto out_pdb;
     }
 
     if (fill_header(&header, &ps, &vs, KdDebuggerDataBlock, kdbg,
             KdVersionBlock, qemu_elf.state_nr)) {
-        err = 1;
         goto out_kdbg;
     }
 
     if (fill_context(kdbg, &vs, &qemu_elf)) {
-        err = 1;
         goto out_kdbg;
     }
 
     if (write_dump(&ps, &header, argv[2])) {
         eprintf("Failed to save dump\n");
-        err = 1;
         goto out_kdbg;
     }
 
+    err = 0;
+
 out_kdbg:
     g_free(kdbg);
 out_pdb: