core: blob+stream: Store stream/blob hashes

Signed-off-by: Chloe M. <chloe@mirocom.org>

Makefile

@@ -8,6 +8,8 @@ DFILES = $(CFILES:.c=.d)
 OFILES = $(CFILES:.c=.o)
 
 CC = gcc
+LIBS = $(shell pkg-config --libs "openssl")
+
 CFLAGS =		\
 	-Wall		\
 	-pedantic	\
@@ -19,7 +21,7 @@ all: blobchain
 
 .PHONY: blobchain
 blobchain: $(OFILES)
-	$(CC) $^ -o $@
+	$(CC) $(LIBS) $^ -o $@
 
 -include $(DFILES)
 %.o: %.c

core/blob_list.c

@@ -3,10 +3,25 @@
  * Provided under the BSD-3 clause
  */
 
+#include <stdio.h>
 #include <errno.h>
+#include <stdlib.h>
 #include "blobchain/blob.h"
 #include "blobchain/memlib.h"
 
+static void
+dump_bytes(void *buf, size_t len)
+{
+    char *p = buf;
+    size_t i = 0;
+
+    while ((i++) < len) {
+        printf("%02X ", p[i] & 0xFF);
+    }
+
+    printf("\n");
+}
+
 int
 blob_list_init(struct blob_list *lp)
 {
@@ -44,5 +59,50 @@ blob_list_append(struct blob_list *lp, struct blob *blob)
 
     ++lp->count;
     return 0;
-    return 0;
+}
+
+void
+blob_list_destroy(struct blob_list *lp)
+{
+    struct blob *bp, *tmp;
+
+    if (lp == NULL) {
+        return;
+    }
+
+    bp = lp->head;
+    while (bp != NULL) {
+        tmp = bp;
+        bp = bp->next;
+
+        free(tmp->data);
+        free(tmp);
+    }
+}
+
+void
+blob_list_dump(struct blob_list *lp)
+{
+    const size_t DUMP_SIZE = 4;
+    struct blob *blob;
+    size_t count = 0;
+
+    if (lp == NULL) {
+        return;
+    }
+
+    blob = lp->head;
+    while (blob != NULL) {
+        printf("blob %zd/%zd\n", count++, lp->count);
+        printf("... length :: %zd\n", blob->length);
+        printf("... hash   :: ");
+        dump_bytes(blob->hash, SHA256_N_BYTES);
+
+        printf("... data   :: ");
+        dump_bytes(blob->data, blob->length < DUMP_SIZE
+            ? blob->length
+            : DUMP_SIZE);
+
+        blob = blob->next;
+    }
 }

core/blob_subr.c

@@ -14,6 +14,7 @@ blob_allocate(struct data_stream *stmp)
 
     bp = xmalloc(sizeof(*bp));
     bp->length = (stmp != NULL) ? stmp->length : 0;
+    bp->next = NULL;
     if (stmp == NULL) {
         bp->data = NULL;
     } else {
@@ -21,5 +22,6 @@ blob_allocate(struct data_stream *stmp)
         memcpy(bp->data, stmp->data, stmp->length);
     }
 
+    memcpy(bp->hash, stmp->hash, SHA256_N_BYTES);
     return bp;
 }

core/blobchain.c

@@ -3,9 +3,19 @@
  * Provided under the BSD-3 clause
  */
 
+#define _DEFAULT_SOURCE
+#include <sys/stat.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dirent.h>
 #include "blobchain/common.h"
+#include "blobchain/stream.h"
+#include "blobchain/blob.h"
+
+/* Input directory path */
+static char *input_dir = NULL;
 
 static void
 help(void)
@@ -13,6 +23,7 @@ help(void)
     printf("usage: ./blobchain <flags>\n");
     printf("... [-h] Display this help menu\n");
     printf("... [-v] Display the version\n");
+    printf("... [-i] Input directory\n");
 }
 
 static void
@@ -21,6 +32,87 @@ version(void)
     printf("Version v%s\n", BLOBCHAIN_VERSION);
 }
 
+static void
+pack_foreach(struct blob_list *blobs, const char *input_dir)
+{
+    struct data_stream stream;
+    char pathbuf[512];
+    struct dirent *dirent;
+    DIR *dir;
+    int error;
+
+    if (input_dir == NULL) {
+        return;
+    }
+
+    if ((dir = opendir(input_dir)) == NULL) {
+        perror("opendir");
+        return;
+    }
+
+    while ((dirent = readdir(dir)) != NULL) {
+        if (dirent->d_name[0] == '.') {
+            continue;
+        }
+
+        switch (dirent->d_type) {
+        case DT_DIR:
+            snprintf(pathbuf, sizeof(pathbuf), "%s/%s", input_dir, dirent->d_name);
+            pack_foreach(blobs, pathbuf);
+            printf("[d] %s\n", pathbuf);
+            break;
+        case DT_REG:
+            snprintf(pathbuf, sizeof(pathbuf), "%s/%s", input_dir, dirent->d_name);
+            printf("[r] %s\n", pathbuf);
+
+            error = stream_from_file(&stream, pathbuf);
+            if (error < 0) {
+                printf("fatal: could not create stream from '%s'\n", pathbuf);
+                return;
+            }
+
+            error = blob_list_append(blobs, blob_allocate(&stream));
+            if (error < 0) {
+                printf("fatal: failed to append blob '%s'\n", pathbuf);
+                stream_destroy(&stream);
+                continue;
+            }
+
+            stream_destroy(&stream);
+            break;
+        }
+    }
+}
+
+static void
+pack_dir(void)
+{
+    struct stat sb;
+    struct blob_list blobs;
+
+    if (stat(input_dir, &sb) < 0) {
+        perror("stat");
+        return;
+    }
+
+    /* Must be a directory */
+    if (!S_ISDIR(sb.st_mode)) {
+        printf("fatal: given path is not a directory!\n");
+        return;
+    }
+
+    if (blob_list_init(&blobs) < 0) {
+        printf("fatal: failed to initialize blob list...\n");
+        return;
+    }
+
+    pack_foreach(&blobs, input_dir);
+#if BLOBCHAIN_DEBUG
+    blob_list_dump(&blobs);
+#endif  /* BLOBCHAIN_DEBUG */
+    blob_list_destroy(&blobs);
+}
+
 int
 main(int argc, char **argv)
 {
@@ -32,7 +124,7 @@ main(int argc, char **argv)
         return -1;
     }
 
-    while ((opt = getopt(argc, argv, "hv")) != -1) {
+    while ((opt = getopt(argc, argv, "hvi:")) != -1) {
         switch (opt) {
         case 'h':
             help();
@@ -40,8 +132,24 @@ main(int argc, char **argv)
         case 'v':
             version();
             return -1;
+        case 'i':
+            input_dir = strdup(optarg);
+            if (input_dir == NULL) {
+                printf("fatal: out of memory\n");
+                return -1;
+            }
+
+            break;
         }
     }
 
+    if (input_dir == NULL) {
+        printf("fatal: expected input directory\n");
+        help();
+        return -1;
+    }
+
+    pack_dir();
+    free(input_dir);
     return 0;
 }

core/stream_file.c

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause
+ */
+
+#include <sys/stat.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <openssl/sha.h>
+#include "blobchain/memlib.h"
+#include "blobchain/stream.h"
+
+int
+stream_from_file(struct data_stream *stmp, const char *path)
+{
+    struct stat sb;
+    void *p;
+    ssize_t readlen;
+    int error, fd;
+
+    if (stmp == NULL || path == NULL) {
+        errno = -EINVAL;
+        return -1;
+    }
+
+    error = stat(path, &sb);
+    if (error < 0) {
+        perror("stat");
+        return -1;
+    }
+
+    fd = open(path, O_RDONLY);
+    if (fd < 0) {
+        perror("open");
+        return -1;
+    }
+
+    /*
+     * Now we want to allocate a whole block of memory to
+     * contain the entire file.
+     *
+     * XXX: For this reason, it is a good idea to only work with
+     *      one file at a time to avoid saturating all of your RAM...
+     */
+    p = xmalloc(sb.st_size);
+    stmp->length = sb.st_size;
+    stmp->data = p;
+
+    readlen = read(fd, p, stmp->length);
+    if (readlen < 0) {
+        perror("read");
+        close(fd);
+        free(p);
+        return -1;
+    }
+
+    SHA256(stmp->data, stmp->length, stmp->hash);
+    return 0;
+}
+
+void
+stream_destroy(struct data_stream *stmp)
+{
+    if (stmp == NULL) {
+        return;
+    }
+
+    if (stmp->data == NULL) {
+        return;
+    }
+
+    free(stmp->data);
+    stmp->length = 0;
+    stmp->data = NULL;
+}

inc/blobchain/blob.h

@@ -9,17 +9,20 @@
 #include <stdint.h>
 #include <stddef.h>
 #include "blobchain/stream.h"
+#include "blobchain/common.h"
 
 /*
  * Represents a single blob of data
  *
  * @data:   Buffer containing blob data
  * @length: Length of blob
+ * @hash:   Hash of file contents
  * @next:   Next blob
  */
 struct blob {
     void *data;
     size_t length;
+    uint8_t hash[SHA256_N_BYTES];
     struct blob *next;
 };
 
@@ -60,4 +63,18 @@ int blob_list_append(struct blob_list *lp, struct blob *blob);
  */
 int blob_list_init(struct blob_list *lp);
 
+/*
+ * Destroy a blob list
+ *
+ * @lp: Bloblist to destroy
+ */
+void blob_list_destroy(struct blob_list *lp);
+
+/*
+ * Dump a blob list for debugging purposes
+ *
+ * @lp: Blob list to dump
+ */
+void blob_list_dump(struct blob_list *lp);
+
 #endif  /* !BLOBCHAIN_BLOB_H */

inc/blobchain/common.h

@@ -6,6 +6,9 @@
 #ifndef BLOBCHAIN_COMMON_H
 #define BLOBCHAIN_COMMON_H 1
 
+#define SHA256_N_BYTES 32
+
+#define BLOBCHAIN_DEBUG 1
 #define BLOBCHAIN_VERSION "0.0.1"
 
 #endif  /* !BLOBCHAIN_COMMON_H */

inc/blobchain/stream.h

@@ -6,17 +6,36 @@
 #ifndef BLOBCHAIN_STREAM_H
 #define BLOBCHAIN_STREAM_H 1
 
+#include <stdint.h>
 #include <stddef.h>
+#include "blobchain/common.h"
 
 /*
  * Represents a data stream
  *
  * @data:   Data buffer
  * @length: Number of bytes in data buffer
+ * @hash:   SHA256 hash of file contents
  */
 struct data_stream {
     void *data;
     size_t length;
+    uint8_t hash[SHA256_N_BYTES];
 };
 
+/*
+ * Obtain a stream from a file
+ *
+ * @stmp: Stream pointer result
+ * @path: Path of file to obtain stream from
+ *
+ * Returns zero on success
+ */
+int stream_from_file(struct data_stream *stmp, const char *path);
+
+/*
+ * Destroy a data stream
+ */
+void stream_destroy(struct data_stream *stmp);
+
 #endif  /* !BLOBCHAIN_STREAM_H */