[llvm] [LLVM-C] Add binding to `BitcodeReader::getBitcodeProducerString` (PR #166063)

[Michal R via llvm-commits]

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@@ -135,3 +134,36 @@ int llvm_module_list_globals(void) {
 
   return 0;
 }
+
+int llvm_module_get_producer_string(void) {
+  LLVMMemoryBufferRef MB;
+  char *Msg = NULL;
+  if (LLVMCreateMemoryBufferWithSTDIN(&MB, &Msg)) {
+    fprintf(stderr, "Error reading file: %s\n", Msg);
+    LLVMDisposeMessage(Msg);
+    return 1;
+  }
+
+  char *Producer = NULL;
+  char *Err = NULL;
+  LLVMBool Ret = LLVMGetBitcodeProducerString(MB, &Producer, &Err);
+  LLVMDisposeMemoryBuffer(MB);
+
+  if (Ret) {
+    fprintf(stderr, "Error reading bitcode: %s\n", Err ? Err : "unknown");
+    if (Err)
+      LLVMDisposeMessage(Err);
+    if (Producer)
+      LLVMDisposeMessage(Producer);
+    return 1;
+  }
+
+  if (Producer) {
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vadorovsky wrote:

You're right. I extended the preficate in the  `if` statement above to `Ret || Err` and handled the lack of `Producer` as an error.

https://github.com/llvm/llvm-project/pull/166063