1 files changed, 284 insertions, 218 deletions
diff --git a/src/Common/libzip/zip_source_buffer.c b/src/Common/libzip/zip_source_buffer.c
index 119bc02c..44159536 100644
--- a/src/Common/libzip/zip_source_buffer.c
+++ b/src/Common/libzip/zip_source_buffer.c
@@ -1,9 +1,9 @@
 /*
   zip_source_buffer.c -- create zip data source from buffer
-  Copyright (C) 1999-2018 Dieter Baron and Thomas Klausner
+  Copyright (C) 1999-2022 Dieter Baron and Thomas Klausner
 
   This file is part of libzip, a library to manipulate ZIP archives.
-  The authors can be contacted at <libzip@nih.at>
+  The authors can be contacted at <info@libzip.org>
 
   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
@@ -50,8 +50,8 @@ struct buffer {
 
     zip_uint64_t shared_fragments; /* number of shared fragments */
     struct buffer *shared_buffer;  /* buffer fragments are shared with */
-    zip_uint64_t size;             /* size of buffer */
 
+    zip_uint64_t size;             /* size of buffer */
     zip_uint64_t offset;           /* current offset in buffer */
     zip_uint64_t current_fragment; /* fragment current offset is in */
 };
@@ -61,6 +61,7 @@ typedef struct buffer buffer_t;
 struct read_data {
     zip_error_t error;
     time_t mtime;
+    zip_file_attributes_t attributes;
     buffer_t *in;
     buffer_t *out;
 };
@@ -79,200 +80,240 @@ static zip_int64_t buffer_write(buffer_t *buffer, const zip_uint8_t *data, zip_u
 
 static zip_int64_t read_data(void *, void *, zip_uint64_t, zip_source_cmd_t);
 
+zip_source_t *zip_source_buffer_with_attributes_create(const void *data, zip_uint64_t len, int freep, zip_file_attributes_t *attributes, zip_error_t *error);
+zip_source_t *zip_source_buffer_fragment_with_attributes_create(const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int freep, zip_file_attributes_t *attributes, zip_error_t *error);
+
 
 ZIP_EXTERN zip_source_t *
 zip_source_buffer(zip_t *za, const void *data, zip_uint64_t len, int freep) {
     if (za == NULL)
-	return NULL;
+        return NULL;
 
-    return zip_source_buffer_create(data, len, freep, &za->error);
+    return zip_source_buffer_with_attributes_create(data, len, freep, NULL, &za->error);
 }
 
 
 ZIP_EXTERN zip_source_t *
 zip_source_buffer_create(const void *data, zip_uint64_t len, int freep, zip_error_t *error) {
+    return zip_source_buffer_with_attributes_create(data, len, freep, NULL, error);
+}
+
+
+zip_source_t *
+zip_source_buffer_with_attributes_create(const void *data, zip_uint64_t len, int freep, zip_file_attributes_t *attributes, zip_error_t *error) {
     zip_buffer_fragment_t fragment;
 
-    if (data == NULL && len > 0) {
-	zip_error_set(error, ZIP_ER_INVAL, 0);
-	return NULL;
+    if (data == NULL) {
+        if (len > 0) {
+            zip_error_set(error, ZIP_ER_INVAL, 0);
+            return NULL;
+        }
+
+        return zip_source_buffer_fragment_with_attributes_create(NULL, 0, freep, attributes, error);
     }
 
     fragment.data = (zip_uint8_t *)data;
     fragment.length = len;
 
-    return zip_source_buffer_fragment_create(&fragment, 1, freep, error);
+    return zip_source_buffer_fragment_with_attributes_create(&fragment, 1, freep, attributes, error);
 }
 
 
 ZIP_EXTERN zip_source_t *
 zip_source_buffer_fragment(zip_t *za, const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int freep) {
     if (za == NULL) {
-	return NULL;
+        return NULL;
     }
 
-    return zip_source_buffer_fragment_create(fragments, nfragments, freep, &za->error);
+    return zip_source_buffer_fragment_with_attributes_create(fragments, nfragments, freep, NULL, &za->error);
 }
 
 
 ZIP_EXTERN zip_source_t *
 zip_source_buffer_fragment_create(const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int freep, zip_error_t *error) {
+    return zip_source_buffer_fragment_with_attributes_create(fragments, nfragments, freep, NULL, error);
+}
+
+zip_source_t *
+zip_source_buffer_fragment_with_attributes_create(const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int freep, zip_file_attributes_t *attributes, zip_error_t *error) {
     struct read_data *ctx;
     zip_source_t *zs;
     buffer_t *buffer;
 
     if (fragments == NULL && nfragments > 0) {
-	zip_error_set(error, ZIP_ER_INVAL, 0);
-	return NULL;
+        zip_error_set(error, ZIP_ER_INVAL, 0);
+        return NULL;
     }
 
     if ((buffer = buffer_new(fragments, nfragments, freep, error)) == NULL) {
-	return NULL;
+        return NULL;
     }
 
     if ((ctx = (struct read_data *)malloc(sizeof(*ctx))) == NULL) {
-	zip_error_set(error, ZIP_ER_MEMORY, 0);
-	buffer_free(buffer);
-	return NULL;
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        buffer_free(buffer);
+        return NULL;
     }
 
     ctx->in = buffer;
     ctx->out = NULL;
     ctx->mtime = time(NULL);
+    if (attributes) {
+        (void)memcpy_s(&ctx->attributes, sizeof(ctx->attributes), attributes, sizeof(ctx->attributes));
+    }
+    else {
+        zip_file_attributes_init(&ctx->attributes);
+    }
     zip_error_init(&ctx->error);
 
     if ((zs = zip_source_function_create(read_data, ctx, error)) == NULL) {
-	buffer_free(ctx->in);
-	free(ctx);
-	return NULL;
+        buffer_free(ctx->in);
+        free(ctx);
+        return NULL;
     }
 
     return zs;
 }
 
 
+zip_source_t *
+zip_source_buffer_with_attributes(zip_t *za, const void *data, zip_uint64_t len, int freep, zip_file_attributes_t *attributes) {
+    return zip_source_buffer_with_attributes_create(data, len, freep, attributes, &za->error);
+}
+
 static zip_int64_t
 read_data(void *state, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
     struct read_data *ctx = (struct read_data *)state;
 
     switch (cmd) {
     case ZIP_SOURCE_BEGIN_WRITE:
-	if ((ctx->out = buffer_new(NULL, 0, 0, &ctx->error)) == NULL) {
-	    return -1;
-	}
-	ctx->out->offset = 0;
-	ctx->out->current_fragment = 0;
-	return 0;
+        if ((ctx->out = buffer_new(NULL, 0, 0, &ctx->error)) == NULL) {
+            return -1;
+        }
+        ctx->out->offset = 0;
+        ctx->out->current_fragment = 0;
+        return 0;
 
     case ZIP_SOURCE_BEGIN_WRITE_CLONING:
-	if ((ctx->out = buffer_clone(ctx->in, len, &ctx->error)) == NULL) {
-	    return -1;
-	}
-	ctx->out->offset = len;
-	ctx->out->current_fragment = ctx->out->nfragments;
-	return 0;
+        if ((ctx->out = buffer_clone(ctx->in, len, &ctx->error)) == NULL) {
+            return -1;
+        }
+        ctx->out->offset = len;
+        ctx->out->current_fragment = ctx->out->nfragments;
+        return 0;
 
     case ZIP_SOURCE_CLOSE:
-	return 0;
+        return 0;
 
     case ZIP_SOURCE_COMMIT_WRITE:
-	buffer_free(ctx->in);
-	ctx->in = ctx->out;
-	ctx->out = NULL;
-	return 0;
+        buffer_free(ctx->in);
+        ctx->in = ctx->out;
+        ctx->out = NULL;
+        return 0;
 
     case ZIP_SOURCE_ERROR:
-	return zip_error_to_data(&ctx->error, data, len);
+        return zip_error_to_data(&ctx->error, data, len);
 
     case ZIP_SOURCE_FREE:
-	buffer_free(ctx->in);
-	buffer_free(ctx->out);
-	free(ctx);
-	return 0;
+        buffer_free(ctx->in);
+        buffer_free(ctx->out);
+        free(ctx);
+        return 0;
+
+    case ZIP_SOURCE_GET_FILE_ATTRIBUTES: {
+        if (len < sizeof(ctx->attributes)) {
+            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
+            return -1;
+        }
+
+        (void)memcpy_s(data, sizeof(ctx->attributes), &ctx->attributes, sizeof(ctx->attributes));
+
+        return sizeof(ctx->attributes);
+    }
 
     case ZIP_SOURCE_OPEN:
-	ctx->in->offset = 0;
-	ctx->in->current_fragment = 0;
-	return 0;
+        ctx->in->offset = 0;
+        ctx->in->current_fragment = 0;
+        return 0;
 
     case ZIP_SOURCE_READ:
-	if (len > ZIP_INT64_MAX) {
-	    zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
-	    return -1;
-	}
-	return buffer_read(ctx->in, data, len);
+        if (len > ZIP_INT64_MAX) {
+            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
+            return -1;
+        }
+        return buffer_read(ctx->in, data, len);
 
     case ZIP_SOURCE_REMOVE: {
-	buffer_t *empty = buffer_new(NULL, 0, 0, &ctx->error);
-	if (empty == NULL) {
-	    return -1;
-	}
+        buffer_t *empty = buffer_new(NULL, 0, 0, &ctx->error);
+        if (empty == NULL) {
+            return -1;
+        }
 
-	buffer_free(ctx->in);
-	ctx->in = empty;
-	return 0;
+        buffer_free(ctx->in);
+        ctx->in = empty;
+        return 0;
     }
 
     case ZIP_SOURCE_ROLLBACK_WRITE:
-	buffer_free(ctx->out);
-	ctx->out = NULL;
-	return 0;
+        buffer_free(ctx->out);
+        ctx->out = NULL;
+        return 0;
 
     case ZIP_SOURCE_SEEK:
-	return buffer_seek(ctx->in, data, len, &ctx->error);
+        return buffer_seek(ctx->in, data, len, &ctx->error);
 
     case ZIP_SOURCE_SEEK_WRITE:
-	return buffer_seek(ctx->out, data, len, &ctx->error);
+        return buffer_seek(ctx->out, data, len, &ctx->error);
 
     case ZIP_SOURCE_STAT: {
-	zip_stat_t *st;
+        zip_stat_t *st;
 
-	if (len < sizeof(*st)) {
-	    zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
-	    return -1;
-	}
+        if (len < sizeof(*st)) {
+            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
+            return -1;
+        }
 
-	st = (zip_stat_t *)data;
+        st = (zip_stat_t *)data;
 
-	zip_stat_init(st);
-	st->mtime = ctx->mtime;
-	st->size = ctx->in->size;
-	st->comp_size = st->size;
-	st->comp_method = ZIP_CM_STORE;
-	st->encryption_method = ZIP_EM_NONE;
-	st->valid = ZIP_STAT_MTIME | ZIP_STAT_SIZE | ZIP_STAT_COMP_SIZE | ZIP_STAT_COMP_METHOD | ZIP_STAT_ENCRYPTION_METHOD;
+        zip_stat_init(st);
+        st->mtime = ctx->mtime;
+        st->size = ctx->in->size;
+        st->comp_size = st->size;
+        st->comp_method = ZIP_CM_STORE;
+        st->encryption_method = ZIP_EM_NONE;
+        st->valid = ZIP_STAT_MTIME | ZIP_STAT_SIZE | ZIP_STAT_COMP_SIZE | ZIP_STAT_COMP_METHOD | ZIP_STAT_ENCRYPTION_METHOD;
 
-	return sizeof(*st);
+        return sizeof(*st);
     }
 
     case ZIP_SOURCE_SUPPORTS:
-	return zip_source_make_command_bitmap(ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_CLOSE, ZIP_SOURCE_STAT, ZIP_SOURCE_ERROR, ZIP_SOURCE_FREE, ZIP_SOURCE_SEEK, ZIP_SOURCE_TELL, ZIP_SOURCE_BEGIN_WRITE, ZIP_SOURCE_BEGIN_WRITE_CLONING, ZIP_SOURCE_COMMIT_WRITE, ZIP_SOURCE_REMOVE, ZIP_SOURCE_ROLLBACK_WRITE, ZIP_SOURCE_SEEK_WRITE, ZIP_SOURCE_TELL_WRITE, ZIP_SOURCE_WRITE, -1);
+        return zip_source_make_command_bitmap(ZIP_SOURCE_GET_FILE_ATTRIBUTES, ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_CLOSE, ZIP_SOURCE_STAT, ZIP_SOURCE_ERROR, ZIP_SOURCE_FREE, ZIP_SOURCE_SEEK, ZIP_SOURCE_TELL, ZIP_SOURCE_BEGIN_WRITE, ZIP_SOURCE_BEGIN_WRITE_CLONING, ZIP_SOURCE_COMMIT_WRITE, ZIP_SOURCE_REMOVE, ZIP_SOURCE_ROLLBACK_WRITE, ZIP_SOURCE_SEEK_WRITE, ZIP_SOURCE_TELL_WRITE, ZIP_SOURCE_WRITE, ZIP_SOURCE_SUPPORTS_REOPEN, -1);
 
     case ZIP_SOURCE_TELL:
-	if (ctx->in->offset > ZIP_INT64_MAX) {
-	    zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);
-	    return -1;
-	}
-	return (zip_int64_t)ctx->in->offset;
+        if (ctx->in->offset > ZIP_INT64_MAX) {
+            zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);
+            return -1;
+        }
+        return (zip_int64_t)ctx->in->offset;
 
 
     case ZIP_SOURCE_TELL_WRITE:
-	if (ctx->out->offset > ZIP_INT64_MAX) {
-	    zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);
-	    return -1;
-	}
-	return (zip_int64_t)ctx->out->offset;
+        if (ctx->out->offset > ZIP_INT64_MAX) {
+            zip_error_set(&ctx->error, ZIP_ER_TELL, EOVERFLOW);
+            return -1;
+        }
+        return (zip_int64_t)ctx->out->offset;
 
     case ZIP_SOURCE_WRITE:
-	if (len > ZIP_INT64_MAX) {
-	    zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
-	    return -1;
-	}
-	return buffer_write(ctx->out, data, len, &ctx->error);
+        if (len > ZIP_INT64_MAX) {
+            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
+            return -1;
+        }
+        return buffer_write(ctx->out, data, len, &ctx->error);
 
     default:
-	zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
-	return -1;
+        zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
+        return -1;
     }
 }
 
@@ -283,50 +324,51 @@ buffer_clone(buffer_t *buffer, zip_uint64_t offset, zip_error_t *error) {
     buffer_t *clone;
 
     if (offset == 0) {
-	return buffer_new(NULL, 0, 1, error);
+        return buffer_new(NULL, 0, 1, error);
     }
 
     if (offset > buffer->size) {
-	zip_error_set(error, ZIP_ER_INVAL, 0);
-	return NULL;
+        zip_error_set(error, ZIP_ER_INVAL, 0);
+        return NULL;
     }
     if (buffer->shared_buffer != NULL) {
-	zip_error_set(error, ZIP_ER_INUSE, 0);
-	return NULL;
+        zip_error_set(error, ZIP_ER_INUSE, 0);
+        return NULL;
     }
 
     fragment = buffer_find_fragment(buffer, offset);
     fragment_offset = offset - buffer->fragment_offsets[fragment];
 
     if (fragment_offset == 0) {
-	fragment--;
-	fragment_offset = buffer->fragments[fragment].length;
+        fragment--;
+        fragment_offset = buffer->fragments[fragment].length;
     }
 
+    /* TODO: This should also consider the length of the fully shared fragments */
     waste = buffer->fragments[fragment].length - fragment_offset;
     if (waste > offset) {
-	zip_error_set(error, ZIP_ER_OPNOTSUPP, 0);
-	return NULL;
+        zip_error_set(error, ZIP_ER_OPNOTSUPP, 0);
+        return NULL;
     }
 
     if ((clone = buffer_new(buffer->fragments, fragment + 1, 0, error)) == NULL) {
-	return NULL;
+        return NULL;
     }
 
 #ifndef __clang_analyzer__
     /* clone->fragments can't be null, since it was created with at least one fragment */
-    clone->fragments[clone->nfragments - 1].length = fragment_offset;
+    clone->fragments[fragment].length = fragment_offset;
 #endif
     clone->fragment_offsets[clone->nfragments] = offset;
     clone->size = offset;
 
-    clone->first_owned_fragment = ZIP_MIN(buffer->first_owned_fragment, clone->nfragments - 1);
+    clone->first_owned_fragment = ZIP_MIN(buffer->first_owned_fragment, clone->nfragments);
 
     buffer->shared_buffer = clone;
     clone->shared_buffer = buffer;
-    buffer->shared_fragments = clone->nfragments;
+    buffer->shared_fragments = fragment + 1;
     clone->shared_fragments = fragment + 1;
-
+    
     return clone;
 }
 
@@ -335,20 +377,24 @@ static zip_uint64_t
 buffer_find_fragment(const buffer_t *buffer, zip_uint64_t offset) {
     zip_uint64_t low, high, mid;
 
+    if (buffer->nfragments == 0) {
+        return 0;
+    }
+
     low = 0;
     high = buffer->nfragments - 1;
 
     while (low < high) {
-	mid = (high - low) / 2 + low;
-	if (buffer->fragment_offsets[mid] > offset) {
-	    high = mid - 1;
-	}
-	else if (mid == buffer->nfragments || buffer->fragment_offsets[mid + 1] > offset) {
-	    return mid;
-	}
-	else {
-	    low = mid + 1;
-	}
+        mid = (high - low) / 2 + low;
+        if (buffer->fragment_offsets[mid] > offset) {
+            high = mid - 1;
+        }
+        else if (mid == buffer->nfragments || buffer->fragment_offsets[mid + 1] > offset) {
+            return mid;
+        }
+        else {
+            low = mid + 1;
+        }
     }
 
     return low;
@@ -360,18 +406,18 @@ buffer_free(buffer_t *buffer) {
     zip_uint64_t i;
 
     if (buffer == NULL) {
-	return;
+        return;
     }
 
     if (buffer->shared_buffer != NULL) {
-	buffer->shared_buffer->shared_buffer = NULL;
-	buffer->shared_buffer->shared_fragments = 0;
+        buffer->shared_buffer->shared_buffer = NULL;
+        buffer->shared_buffer->shared_fragments = 0;
 
-	buffer->first_owned_fragment = ZIP_MAX(buffer->first_owned_fragment, buffer->shared_fragments);
+        buffer->first_owned_fragment = ZIP_MAX(buffer->first_owned_fragment, buffer->shared_fragments);
     }
 
     for (i = buffer->first_owned_fragment; i < buffer->nfragments; i++) {
-	free(buffer->fragments[i].data);
+        free(buffer->fragments[i].data);
     }
     free(buffer->fragments);
     free(buffer->fragment_offsets);
@@ -383,19 +429,29 @@ static bool
 buffer_grow_fragments(buffer_t *buffer, zip_uint64_t capacity, zip_error_t *error) {
     zip_buffer_fragment_t *fragments;
     zip_uint64_t *offsets;
+    zip_uint64_t fragments_size;
+    zip_uint64_t offsets_size;
 
     if (capacity < buffer->fragments_capacity) {
-	return true;
+        return true;
     }
 
-    if ((fragments = realloc(buffer->fragments, sizeof(buffer->fragments[0]) * capacity)) == NULL) {
-	zip_error_set(error, ZIP_ER_MEMORY, 0);
-	return false;
+    fragments_size = sizeof(buffer->fragments[0]) * capacity;
+    offsets_size = sizeof(buffer->fragment_offsets[0]) * (capacity + 1);
+
+    if (capacity == ZIP_UINT64_MAX || fragments_size < capacity || fragments_size > SIZE_MAX|| offsets_size < capacity || offsets_size > SIZE_MAX) {
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        return false;
+    }
+
+    if ((fragments = realloc(buffer->fragments, (size_t)fragments_size)) == NULL) {
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        return false;
     }
     buffer->fragments = fragments;
-    if ((offsets = realloc(buffer->fragment_offsets, sizeof(buffer->fragment_offsets[0]) * (capacity + 1))) == NULL) {
-	zip_error_set(error, ZIP_ER_MEMORY, 0);
-	return false;
+    if ((offsets = realloc(buffer->fragment_offsets, (size_t)offsets_size)) == NULL) {
+        zip_error_set(error, ZIP_ER_MEMORY, 0);
+        return false;
     }
     buffer->fragment_offsets = offsets;
     buffer->fragments_capacity = capacity;
@@ -409,7 +465,7 @@ buffer_new(const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int
     buffer_t *buffer;
 
     if ((buffer = malloc(sizeof(*buffer))) == NULL) {
-	return NULL;
+        return NULL;
     }
 
     buffer->offset = 0;
@@ -423,42 +479,43 @@ buffer_new(const zip_buffer_fragment_t *fragments, zip_uint64_t nfragments, int
     buffer->shared_fragments = 0;
 
     if (nfragments == 0) {
-	if ((buffer->fragment_offsets = malloc(sizeof(buffer->fragment_offsets[0]))) == NULL) {
-	    free(buffer);
-	    zip_error_set(error, ZIP_ER_MEMORY, 0);
-	    return NULL;
-	}
-	buffer->fragment_offsets[0] = 0;
+        if ((buffer->fragment_offsets = malloc(sizeof(buffer->fragment_offsets[0]))) == NULL) {
+            free(buffer);
+            zip_error_set(error, ZIP_ER_MEMORY, 0);
+            return NULL;
+        }
+        buffer->fragment_offsets[0] = 0;
     }
     else {
-	zip_uint64_t i, j, offset;
-
-	if (!buffer_grow_fragments(buffer, nfragments, NULL)) {
-	    zip_error_set(error, ZIP_ER_MEMORY, 0);
-	    buffer_free(buffer);
-	    return NULL;
-	}
-
-	offset = 0;
-	for (i = 0, j = 0; i < nfragments; i++) {
-	    if (fragments[i].length == 0) {
-		continue;
-	    }
-	    if (fragments[i].data == NULL) {
-		zip_error_set(error, ZIP_ER_INVAL, 0);
-		buffer_free(buffer);
-		return NULL;
-	    }
-	    buffer->fragments[j].data = fragments[i].data;
-	    buffer->fragments[j].length = fragments[i].length;
-	    buffer->fragment_offsets[i] = offset;
-	    offset += fragments[i].length;
-	    j++;
-	}
-	buffer->nfragments = j;
-	buffer->first_owned_fragment = free_data ? 0 : buffer->nfragments;
-	buffer->fragment_offsets[nfragments] = offset;
-	buffer->size = offset;
+        zip_uint64_t i, j, offset;
+
+        if (!buffer_grow_fragments(buffer, nfragments, NULL)) {
+            zip_error_set(error, ZIP_ER_MEMORY, 0);
+            buffer_free(buffer);
+            return NULL;
+        }
+
+        offset = 0;
+        for (i = 0, j = 0; i < nfragments; i++) {
+            if (fragments[i].length == 0) {
+                continue;
+            }
+            if (fragments[i].data == NULL) {
+                zip_error_set(error, ZIP_ER_INVAL, 0);
+                buffer_free(buffer);
+                return NULL;
+            }
+            buffer->fragments[j].data = fragments[i].data;
+            buffer->fragments[j].length = fragments[i].length;
+            buffer->fragment_offsets[i] = offset;
+            /* TODO: overflow */
+            offset += fragments[i].length;
+            j++;
+        }
+        buffer->nfragments = j;
+        buffer->first_owned_fragment = free_data ? 0 : buffer->nfragments;
+        buffer->fragment_offsets[buffer->nfragments] = offset;
+        buffer->size = offset;
     }
 
     return buffer;
@@ -471,25 +528,28 @@ buffer_read(buffer_t *buffer, zip_uint8_t *data, zip_uint64_t length) {
     length = ZIP_MIN(length, buffer->size - buffer->offset);
 
     if (length == 0) {
-	return 0;
+        return 0;
     }
     if (length > ZIP_INT64_MAX) {
-	return -1;
+        return -1;
     }
 
     i = buffer->current_fragment;
     fragment_offset = buffer->offset - buffer->fragment_offsets[i];
     n = 0;
     while (n < length) {
-	zip_uint64_t left = ZIP_MIN(length - n, buffer->fragments[i].length - fragment_offset);
+        zip_uint64_t left = ZIP_MIN(length - n, buffer->fragments[i].length - fragment_offset);
+#if ZIP_UINT64_MAX > SIZE_MAX
+        left = ZIP_MIN(left, SIZE_MAX);
+#endif
 
-	memcpy(data + n, buffer->fragments[i].data + fragment_offset, left);
+        (void)memcpy_s(data + n, (size_t)left, buffer->fragments[i].data + fragment_offset, (size_t)left);
 
-	if (left == buffer->fragments[i].length - fragment_offset) {
-	    i++;
-	}
-	n += left;
-	fragment_offset = 0;
+        if (left == buffer->fragments[i].length - fragment_offset) {
+            i++;
+        }
+        n += left;
+        fragment_offset = 0;
     }
 
     buffer->offset += n;
@@ -503,7 +563,7 @@ buffer_seek(buffer_t *buffer, void *data, zip_uint64_t len, zip_error_t *error)
     zip_int64_t new_offset = zip_source_seek_compute_offset(buffer->offset, buffer->size, data, len, error);
 
     if (new_offset < 0) {
-	return -1;
+        return -1;
     }
 
     buffer->offset = (zip_uint64_t)new_offset;
@@ -514,66 +574,72 @@ buffer_seek(buffer_t *buffer, void *data, zip_uint64_t len, zip_error_t *error)
 
 static zip_int64_t
 buffer_write(buffer_t *buffer, const zip_uint8_t *data, zip_uint64_t length, zip_error_t *error) {
-    zip_uint64_t n, i, fragment_offset, capacity;
+    zip_uint64_t copied, i, fragment_offset, capacity;
 
     if (buffer->offset + length + WRITE_FRAGMENT_SIZE - 1 < length) {
-	zip_error_set(error, ZIP_ER_INVAL, 0);
-	return -1;
+        zip_error_set(error, ZIP_ER_INVAL, 0);
+        return -1;
     }
 
     /* grow buffer if needed */
     capacity = buffer_capacity(buffer);
     if (buffer->offset + length > capacity) {
-	zip_uint64_t needed_fragments = buffer->nfragments + (length - (capacity - buffer->offset) + WRITE_FRAGMENT_SIZE - 1) / WRITE_FRAGMENT_SIZE;
-
-	if (needed_fragments > buffer->fragments_capacity) {
-	    zip_uint64_t new_capacity = buffer->fragments_capacity;
-
-	    if (new_capacity == 0) {
-		new_capacity = 16;
-	    }
-	    while (new_capacity < needed_fragments) {
-		new_capacity *= 2;
-	    }
-
-	    if (!buffer_grow_fragments(buffer, new_capacity, error)) {
-		zip_error_set(error, ZIP_ER_MEMORY, 0);
-		return -1;
-	    }
-	}
-
-	while (buffer->nfragments < needed_fragments) {
-	    if ((buffer->fragments[buffer->nfragments].data = malloc(WRITE_FRAGMENT_SIZE)) == NULL) {
-		zip_error_set(error, ZIP_ER_MEMORY, 0);
-		return -1;
-	    }
-	    buffer->fragments[buffer->nfragments].length = WRITE_FRAGMENT_SIZE;
-	    buffer->nfragments++;
-	    capacity += WRITE_FRAGMENT_SIZE;
-	    buffer->fragment_offsets[buffer->nfragments] = capacity;
-	}
+        zip_uint64_t needed_fragments = buffer->nfragments + (length - (capacity - buffer->offset) + WRITE_FRAGMENT_SIZE - 1) / WRITE_FRAGMENT_SIZE;
+
+        if (needed_fragments > buffer->fragments_capacity) {
+            zip_uint64_t new_capacity = buffer->fragments_capacity;
+
+            if (new_capacity == 0) {
+                new_capacity = 16;
+            }
+            while (new_capacity < needed_fragments) {
+                new_capacity *= 2;
+            }
+
+            if (!buffer_grow_fragments(buffer, new_capacity, error)) {
+                zip_error_set(error, ZIP_ER_MEMORY, 0);
+                return -1;
+            }
+        }
+
+        while (buffer->nfragments < needed_fragments) {
+            if ((buffer->fragments[buffer->nfragments].data = malloc(WRITE_FRAGMENT_SIZE)) == NULL) {
+                zip_error_set(error, ZIP_ER_MEMORY, 0);
+                return -1;
+            }
+            buffer->fragments[buffer->nfragments].length = WRITE_FRAGMENT_SIZE;
+            buffer->nfragments++;
+            capacity += WRITE_FRAGMENT_SIZE;
+            buffer->fragment_offsets[buffer->nfragments] = capacity;
+        }
     }
 
     i = buffer->current_fragment;
     fragment_offset = buffer->offset - buffer->fragment_offsets[i];
-    n = 0;
-    while (n < length) {
-	zip_uint64_t left = ZIP_MIN(length - n, buffer->fragments[i].length - fragment_offset);
+    copied = 0;
+    while (copied < length) {
+        zip_uint64_t n = ZIP_MIN(ZIP_MIN(length - copied, buffer->fragments[i].length - fragment_offset), SIZE_MAX);
+#if ZIP_UINT64_MAX > SIZE_MAX
+        n = ZIP_MIN(n, SIZE_MAX);
+#endif
 
-	memcpy(buffer->fragments[i].data + fragment_offset, data + n, left);
+        (void)memcpy_s(buffer->fragments[i].data + fragment_offset, (size_t)n, data + copied, (size_t)n);
 
-	if (left == buffer->fragments[i].length - fragment_offset) {
-	    i++;
-	}
-	n += left;
-	fragment_offset = 0;
+        if (n == buffer->fragments[i].length - fragment_offset) {
+            i++;
+            fragment_offset = 0;
+        }
+        else {
+            fragment_offset += n;
+        }
+        copied += n;
     }
 
-    buffer->offset += n;
+    buffer->offset += copied;
     buffer->current_fragment = i;
     if (buffer->offset > buffer->size) {
-	buffer->size = buffer->offset;
+        buffer->size = buffer->offset;
     }
 
-    return (zip_int64_t)n;
+    return (zip_int64_t)copied;
 }