riffprobe: rewrite and simplify

1 files changed, 20 insertions, 107 deletions

diff --git a/riffprobe/riffprobe.c b/riffprobe/riffprobe.c
index 100b2fa..29918df 100644
--- a/riffprobe/riffprobe.c
+++ b/riffprobe/riffprobe.c
@@ -1,10 +1,11 @@
 // ================================================================================================
-// Basic RIFF/WAVE file traversal. Does not decode media data.
+// Basic RIFF/WAVE file traversal. Does not do any real parsing.
 //
 // ref: https://mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/Docs/riffmci.pdf
 //
 // Changelog:
 //     9/20/2026: Initial release
+//     9/22/2026: Can now accept multiple files
 //
 // License:
 //     SPDX-License-Identifier: 0BSD
@@ -44,29 +45,6 @@ static void die(const char *fmt, ...)
     exit(1);
 }
 
-typedef struct Chunk Chunk;
-struct Chunk
-{
-    uint32_t id;
-    uint32_t size;
-};
-
-// WAVE chunks
-typedef struct WAVE_Fmt WAVE_Fmt;
-struct WAVE_Fmt
-{
-    uint16_t fmt_tag;
-    uint16_t channels;
-    uint32_t samples_per_sec;
-    uint32_t avg_bytes_per_sec;
-    uint16_t block_align;
-};
-
-static bool read_chunk(FILE *fp, Chunk *chunk)
-{
-    return fread(chunk, sizeof(Chunk), 1, fp) == 1;
-}
-
 static const char *unfourcc(uint32_t id)
 {
     static char b[5] = { 0 };
@@ -77,102 +55,37 @@ static const char *unfourcc(uint32_t id)
     return b;
 }
 
-static bool match_id(uint32_t id, const char *fourcc)
-{
-    const char *id_fourcc = unfourcc(id);
-    for (int i = 0; i < 4; ++i)
-    {
-        if (tolower(id_fourcc[i]) != tolower(fourcc[i]))
-            return false;
-    }
-    return true;
-}
-
-static uint32_t pad_size(uint32_t size)
-{
-    if (size % 2 != 0)
-        return size + 1;
-    return size;
-}
-
 int main(int argc, const char **argv)
 {
     if (argc < 2)
         die("no file");
 
-    FILE* fp = fopen(argv[1], "rb");
-    if (!fp)
-        die("failed to open file: %s", strerror(errno));
-
-    fseek(fp, 0, SEEK_END);
-    size_t flen = ftell(fp);
-    fseek(fp, 0, SEEK_SET);
-
-    Chunk root;
-    if (!read_chunk(fp, &root) || !match_id(root.id, "RIFF"))
-        die("unsupported or malformed file");
-    if (root.size + sizeof(Chunk) != flen)
-        printf("file length mismatch\n");
-
-    uint32_t riff_type = 0;
-    fread(&riff_type, sizeof(riff_type), 1, fp);
-    printf("type: %s\n", unfourcc(riff_type));
-
-    Chunk chunk;
-    while (read_chunk(fp, &chunk))
+    for (int i = 1; i < argc; ++i)
     {
-        size_t next_pos = ftell(fp) + pad_size(chunk.size);
-        printf("chunk: %s\n", unfourcc(chunk.id));
-        if (match_id(riff_type, "WAVE") && match_id(chunk.id, "FMT "))
-        {
-            WAVE_Fmt fmt;
-            fread(&fmt, sizeof(fmt), 1, fp);
+        printf("%s:\n", argv[i]);
 
-            printf("    fmt category: %d\n", fmt.fmt_tag);
-            printf("    channels:     %d\n", fmt.channels);
-            printf("    sample rate:  %d\n", fmt.samples_per_sec);
-        }
-        if (match_id(riff_type, "WAVE") && match_id(chunk.id, "FACT")) {
-            uint32_t file_size = 0;
-            fread(&file_size, sizeof(file_size), 1, fp);
-
-            printf("    file size: %d\n", file_size);
-        }
-        if (match_id(chunk.id, "LIST")) {
-            uint32_t list_type = 0;
-            fread(&list_type, sizeof(list_type), 1, fp);
+        FILE* fp = fopen(argv[i], "rb");
+        if (!fp)
+            die("failed to open file: %s", strerror(errno));
 
-            printf("    list type: %s\n", unfourcc(list_type));
+        uint8_t buf[256];
 
-            size_t list_start = ftell(fp);
-            size_t list_end   = list_start + chunk.size - sizeof(list_type);
+        if (fread(buf, 1, 12, fp) != 12)
+            return 1;
 
-            Chunk subchunk;
-            while ((size_t)ftell(fp) < list_end && read_chunk(fp, &subchunk))
-            {
-                size_t next_sub_pos = ftell(fp) + pad_size(subchunk.size);
-                printf("        subchunk: %s\n", unfourcc(subchunk.id));
+        if (memcmp(buf, "RIFF", 4) || memcmp(buf + 8, "WAVE", 4))
+            die("Invalid file");
 
-                if (match_id(subchunk.id, "IART") ||
-                    match_id(subchunk.id, "IGNR") ||
-                    match_id(subchunk.id, "IPRD") ||
-                    match_id(subchunk.id, "ISFT"))
-                {
-                    char buf[1024] = { 0 };
-                    size_t len = sizeof(buf) - 1;
-                    if (subchunk.size < len)
-                        len = subchunk.size;
-                    fread(buf, len, 1, fp);
-                    printf("        data:     %s\n", buf);
-                }
-
-                fseek(fp, next_sub_pos, SEEK_SET);
-            }
+        while (!feof(fp))
+        {
+            if (fread(buf, 1, 8, fp) != 8)
+                break;
+            uint32_t tag  = *(uint32_t *)buf;
+            uint32_t size = *(uint32_t *)(buf + 4);
+            printf("    %s\n", unfourcc(tag));
+            fseek(fp, size, SEEK_CUR);
         }
-        fseek(fp, next_pos, SEEK_SET);
     }
 
-    fclose(fp);
-
     return 0;
 }