lib/memzip: Factor out memzip from teensy/ into lib/memzip.

1 files changed, 106 insertions, 0 deletions

diff --git a/lib/memzip/memzip.c b/lib/memzip/memzip.c
new file mode 100644
index 0000000000..3fbea8e1e9
--- /dev/null
+++ b/lib/memzip/memzip.c
@@ -0,0 +1,106 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include "py/mpconfig.h"
+#include "py/misc.h"
+#include "memzip.h"
+
+extern uint8_t memzip_data[];
+
+const MEMZIP_FILE_HDR *memzip_find_file_header(const char *filename) {
+
+    const MEMZIP_FILE_HDR *file_hdr = (const MEMZIP_FILE_HDR *)memzip_data;
+    uint8_t *mem_data;
+
+    /* Zip file filenames don't have a leading /, so we strip it off */
+
+    if (*filename == '/') {
+        filename++;
+    }
+    while (file_hdr->signature == MEMZIP_FILE_HEADER_SIGNATURE) {
+        const char *file_hdr_filename = (const char *)&file_hdr[1];
+        mem_data = (uint8_t *)file_hdr_filename;
+        mem_data += file_hdr->filename_len;
+        mem_data += file_hdr->extra_len;
+        if (!strncmp(file_hdr_filename, filename, file_hdr->filename_len)) {
+            /* We found a match */
+            return file_hdr;
+        }
+        mem_data += file_hdr->uncompressed_size;
+        file_hdr = (const MEMZIP_FILE_HDR *)mem_data;
+    }
+    return NULL;
+}
+
+bool memzip_is_dir(const char *filename) {
+    const MEMZIP_FILE_HDR *file_hdr = (const MEMZIP_FILE_HDR *)memzip_data;
+    uint8_t *mem_data;
+
+    if (strcmp(filename, "/") == 0) {
+        // The root directory is a directory.
+        return true;
+    }
+
+    // Zip filenames don't have a leading /, so we strip it off
+    if (*filename == '/') {
+        filename++;
+    }
+    size_t filename_len = strlen(filename);
+
+    while (file_hdr->signature == MEMZIP_FILE_HEADER_SIGNATURE) {
+        const char *file_hdr_filename = (const char *)&file_hdr[1];
+        if (filename_len < file_hdr->filename_len &&
+            strncmp(file_hdr_filename, filename, filename_len) == 0 &&
+            file_hdr_filename[filename_len] == '/') {
+            return true;
+        }
+
+        mem_data = (uint8_t *)file_hdr_filename;
+        mem_data += file_hdr->filename_len;
+        mem_data += file_hdr->extra_len;
+        mem_data += file_hdr->uncompressed_size;
+        file_hdr = (const MEMZIP_FILE_HDR *)mem_data;
+    }
+    return NULL;
+
+}
+
+MEMZIP_RESULT memzip_locate(const char *filename, void **data, size_t *len)
+{
+    const MEMZIP_FILE_HDR *file_hdr = memzip_find_file_header(filename);
+    if (file_hdr == NULL) {
+        return MZ_NO_FILE;
+    }
+    if (file_hdr->compression_method != 0) {
+        return MZ_FILE_COMPRESSED;
+    }
+
+    uint8_t *mem_data;
+    mem_data = (uint8_t *)&file_hdr[1];
+    mem_data += file_hdr->filename_len;
+    mem_data += file_hdr->extra_len;
+
+    *data = mem_data;
+    *len = file_hdr->uncompressed_size;
+    return MZ_OK;
+}
+
+MEMZIP_RESULT memzip_stat(const char *path, MEMZIP_FILE_INFO *info) {
+    const MEMZIP_FILE_HDR *file_hdr = memzip_find_file_header(path);
+    if (file_hdr == NULL) {
+        if (memzip_is_dir(path)) {
+            info->file_size = 0;
+            info->last_mod_date = 0;
+            info->last_mod_time = 0;
+            info->is_dir = 1;
+            return MZ_OK;
+        }
+        return MZ_NO_FILE;
+    }
+    info->file_size = file_hdr->uncompressed_size;
+    info->last_mod_date = file_hdr->last_mod_date;
+    info->last_mod_time = file_hdr->last_mod_time;
+    info->is_dir = 0;
+
+    return MZ_OK;
+}