vboot_ref/cgpt: Move mkdir out of flashrom worker func

Small refactor to make it easier to more towards
libflashrom. This makes the call site responsible for
setting up the path for ReadNorFlash().

BUG=b:207808292,b:220079643
BRANCH=none
TEST=`make cgpt`

Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Change-Id: I15fc57e5afca6206b60df92616fd4cdce63b03e3
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3469738
Tested-by: Edward O'Callaghan <quasisec@chromium.org>
Auto-Submit: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-by: Sam McNally <sammc@chromium.org>
Commit-Queue: Edward O'Callaghan <quasisec@chromium.org>

4 files changed, 16 insertions, 18 deletions

diff --git a/cgpt/cgpt_find.c b/cgpt/cgpt_find.c
index 8046aad3..f50908fe 100644
--- a/cgpt/cgpt_find.c
+++ b/cgpt/cgpt_find.c
@@ -243,8 +243,14 @@ static int scan_spi_gpt(CgptFindParams *params) {
           goto cleanup;
         }
       }
+      // Create a temp dir to work in.
+      if (mkdtemp(temp_dir) == NULL) {
+        perror("Cannot create a temporary directory.\n");
+        goto cleanup;
+      }
       if (ReadNorFlash(temp_dir) != 0) {
         perror("ReadNorFlash");
+        RemoveDir(temp_dir);
         goto cleanup;
       }
       char nor_file[64];
diff --git a/cgpt/cgpt_nor.c b/cgpt/cgpt_nor.c
index 76fefe1e..e96ee274 100644
--- a/cgpt/cgpt_nor.c
+++ b/cgpt/cgpt_nor.c
@@ -203,20 +203,11 @@ int RemoveDir(const char *dir) {
 #define FLASHROM_RW_GPT_SEC "RW_GPT_SECONDARY:rw_gpt_2"
 #define FLASHROM_RW_GPT "RW_GPT:rw_gpt"
 
-// Read RW_GPT from NOR flash to "rw_gpt" in a temp dir |temp_dir_template|.
-// |temp_dir_template| is passed to mkdtemp() so it must satisfy all
-// requirements by mkdtemp.
+// Read RW_GPT from NOR flash to "rw_gpt" in a dir.
 // TODO(b:184812319): Replace this function with flashrom_read.
-int ReadNorFlash(char *temp_dir_template) {
+int ReadNorFlash(const char *dir) {
   int ret = 0;
 
-  // Create a temp dir to work in.
-  ret++;
-  if (mkdtemp(temp_dir_template) == NULL) {
-    Error("Cannot create a temporary directory.\n");
-    return ret;
-  }
-
   // Read RW_GPT section from NOR flash to "rw_gpt".
   ret++;
 
@@ -225,7 +216,7 @@ int ReadNorFlash(char *temp_dir_template) {
     Error("Cannot get current directory.\n");
     return ret;
   }
-  if (chdir(temp_dir_template) < 0) {
+  if (chdir(dir) < 0) {
     Error("Cannot change directory.\n");
     goto out_free;
   }
@@ -234,7 +225,6 @@ int ReadNorFlash(char *temp_dir_template) {
   // output.
   if (subprocess_run(argv, &subprocess_null, &subprocess_null, NULL) != 0) {
     Error("Cannot exec flashrom to read from RW_GPT section.\n");
-    RemoveDir(temp_dir_template);
   } else {
     ret = 0;
   }
diff --git a/cgpt/cgpt_nor.h b/cgpt/cgpt_nor.h
index 47460895..93e9ddee 100644
--- a/cgpt/cgpt_nor.h
+++ b/cgpt/cgpt_nor.h
@@ -23,10 +23,8 @@ int ForkExecL(const char *cwd, const char *cmd, ...);
 // Exec "rm" to remove |dir|.
 int RemoveDir(const char *dir);
 
-// Read RW_GPT from NOR flash to "rw_gpt" in a temp dir |temp_dir_template|.
-// |temp_dir_template| is passed to mkdtemp() so it must satisfy all
-// requirements by mkdtemp().
-int ReadNorFlash(char *temp_dir_template);
+// Read RW_GPT from NOR flash to "rw_gpt" in dir.
+int ReadNorFlash(const char *dir);
 
 // Write "rw_gpt" back to NOR flash. We write the file in two parts for safety.
 int WriteNorFlash(const char *dir);
diff --git a/cgpt/cgpt_wrapper.c b/cgpt/cgpt_wrapper.c
index d26682dd..17336c15 100644
--- a/cgpt/cgpt_wrapper.c
+++ b/cgpt/cgpt_wrapper.c
@@ -82,9 +82,13 @@ static int wrap_cgpt(int argc,
   // Create a temp dir to work in.
   ret++;
   char temp_dir[] = "/tmp/cgpt_wrapper.XXXXXX";
-  if (ReadNorFlash(temp_dir) != 0) {
+  if (mkdtemp(temp_dir_template) == NULL) {
+    Error("Cannot create a temporary directory.\n");
     return ret;
   }
+  if (ReadNorFlash(temp_dir) != 0) {
+    goto cleanup;
+  }
   char rw_gpt_path[PATH_MAX];
   if (snprintf(rw_gpt_path, sizeof(rw_gpt_path), "%s/rw_gpt", temp_dir) < 0) {
     goto cleanup;