grk_decompress_detect_format: better error logging

Author: Grok Compression

.vscode/launch.json

@@ -39,6 +39,54 @@
                     "ignoreFailures": true
                 }
             ]
+        },
+        {
+            "name": "crash",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/build/bin/grk_decompress",
+            "args": [
+                "-i",
+                "~/temp/input_01",
+                "-o",
+                "~/temp/input_01.tif",
+                "-v"
+            ],
+            "stopAtEntry": true,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ]
+        },
+        {
+            "name": "dump",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/build/bin/grk_dump",
+            "args": [
+                "-i",
+                "~/src/grok-test-data/input/nonregression/multi_tile_truncated_rgb.jp2",
+                "-o",
+                "~/temp/trunc.txt",
+                "-v"
+            ],
+            "stopAtEntry": true,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ]
         }
     ]
 }

src/lib/codec/jp2/GrkDump.cpp

@@ -172,12 +172,7 @@ static int parseCommandLine(int argc, char** argv, grk_decompress_parameters* pa
 	  {
 		 const char* infile = inputArg.getValue().c_str();
 		 if(!grk_decompress_detect_format(infile, &parameters->decod_format))
-		 {
-			spdlog::error("Unknown input file format: {} \n"
-						  "        Known file formats are *.j2k, *.jp2 or *.jpc",
-						  infile);
 			return 1;
-		 }
 		 if(grk::strcpy_s(parameters->infile, sizeof(parameters->infile), infile) != 0)
 		 {
 			spdlog::error("Path is too long");

src/lib/core/grok.cpp

@@ -283,13 +283,22 @@ bool GRK_CALLCONV grk_decompress_detect_format(const char* fileName, GRK_CODEC_F
 
    auto reader = fopen(fileName, "rb");
    if(!reader)
+   {
+	  Logger::logger_.error("Unable to open file {}.", fileName);
 	  return false;
+   }
 
    bytesRead = fread(buf, 1, 12, reader);
    if(fclose(reader))
+   {
+	  Logger::logger_.error("Unable to close file {}.", fileName);
 	  return false;
+   }
    if(bytesRead != 12)
+   {
+	  Logger::logger_.error("Insufficient bytes to detect JPEG 2000 format in file {}.", fileName);
 	  return false;
+   }
 
    return grk_decompress_buffer_detect_format(buf, 12, fmt);
 }