Scan .modinfo sections of qemu modules,
write module metadata to modinfo.json.
Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
---
qemu-modinfo.c | 270 +++++++++++++++++++++++++++++++++++++++++++++++++
meson.build | 11 ++
2 files changed, 281 insertions(+)
create mode 100644 qemu-modinfo.c
diff --git a/qemu-modinfo.c b/qemu-modinfo.c
new file mode 100644
index 000000000000..611dbdb00683
--- /dev/null
+++ b/qemu-modinfo.c
@@ -0,0 +1,270 @@
+/*
+ * QEMU module parser
+ *
+ * read modules, find modinfo section, parse & store metadata.
+ *
+ * Copyright Red Hat, Inc. 2021
+ *
+ * Authors:
+ * Gerd Hoffmann <kra...@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "elf.h"
+#include <stdint.h>
+#include <dirent.h>
+
+#include "qapi/qapi-types-modules.h"
+#include "qapi/qapi-visit-modules.h"
+#include "qapi/qobject-output-visitor.h"
+#include "qapi/qmp/qjson.h"
+#include "qapi/qmp/qstring.h"
+
+#if INTPTR_MAX == INT32_MAX
+# define Elf_Ehdr Elf32_Ehdr
+# define Elf_Shdr Elf32_Shdr
+# define ELFCLASS ELFCLASS32
+#elif INTPTR_MAX == INT64_MAX
+# define Elf_Ehdr Elf64_Ehdr
+# define Elf_Shdr Elf64_Shdr
+# define ELFCLASS ELFCLASS64
+#else
+# error Huh? Neither 32-bit nor 64-bit host.
+#endif
+
+static const char *moddir = CONFIG_QEMU_MODDIR;
+static const char *dsosuf = CONFIG_HOST_DSOSUF;
+
+static ModuleInfo *modinfo(const char *module, char *info, size_t size)
+{
+ ModuleInfo *modinfo;
+ strList *sl;
+ size_t pos = 0, len;
+
+ modinfo = g_new0(ModuleInfo, 1);
+ modinfo->name = g_strdup(module);
+
+ if (info) {
+ do {
+ if (strncmp(info + pos, "obj=", 4) == 0) {
+ sl = g_new0(strList, 1);
+ sl->value = g_strdup(info + pos + 4);
+ sl->next = modinfo->objs;
+ modinfo->objs = sl;
+ modinfo->has_objs = true;
+ } else if (strncmp(info + pos, "dep=", 4) == 0) {
+ sl = g_new0(strList, 1);
+ sl->value = g_strdup(info + pos + 4);
+ sl->next = modinfo->deps;
+ modinfo->deps = sl;
+ modinfo->has_deps = true;
+ } else if (strncmp(info + pos, "arch=", 5) == 0) {
+ modinfo->arch = g_strdup(info + pos + 5);
+ modinfo->has_arch = true;
+ } else if (strncmp(info + pos, "opts=", 5) == 0) {
+ modinfo->opts = g_strdup(info + pos + 5);
+ modinfo->has_opts = true;
+ } else {
+ fprintf(stderr, "unknown tag: %s\n", info + pos);
+ exit(1);
+ }
+ len = strlen(info + pos) + 1;
+ pos += len;
+ } while (pos < size);
+ }
+
+ return modinfo;
+}
+
+static void elf_read_section_hdr(FILE *fp, Elf_Ehdr *ehdr,
+ int section, Elf_Shdr *shdr)
+{
+ size_t pos, len;
+ int ret;
+
+ pos = ehdr->e_shoff + section * ehdr->e_shentsize;
+ len = MIN(ehdr->e_shentsize, sizeof(*shdr));
+
+ ret = fseek(fp, pos, SEEK_SET);
+ if (ret != 0) {
+ fprintf(stderr, "seek error\n");
+ exit(1);
+ }
+
+ memset(shdr, 0, sizeof(*shdr));
+ ret = fread(shdr, len, 1, fp);
+ if (ret != 1) {
+ fprintf(stderr, "read error\n");
+ exit(1);
+ }
+}
+
+static void *elf_read_section(FILE *fp, Elf_Ehdr *ehdr,
+ int section, size_t *size)
+{
+ Elf_Shdr shdr;
+ void *data;
+ int ret;
+
+ elf_read_section_hdr(fp, ehdr, section, &shdr);
+ if (shdr.sh_offset && shdr.sh_size) {
+ ret = fseek(fp, shdr.sh_offset, SEEK_SET);
+ if (ret != 0) {
+ fprintf(stderr, "seek error\n");
+ exit(1);
+ }
+
+ data = g_malloc(shdr.sh_size);
+ ret = fread(data, shdr.sh_size, 1, fp);
+ if (ret != 1) {
+ fprintf(stderr, "read error\n");
+ exit(1);
+ }
+ *size = shdr.sh_size;
+ } else {
+ data = NULL;
+ *size = 0;
+ }
+ return data;
+}
+
+static ModuleInfo *elf_parse_module(const char *module,
+ const char *filename)
+{
+ Elf_Ehdr ehdr;
+ Elf_Shdr shdr;
+ FILE *fp;
+ int ret, i;
+ char *str;
+ size_t str_size;
+ char *info;
+ size_t info_size;
+
+ fp = fopen(filename, "r");
+ if (NULL == fp) {
+ fprintf(stderr, "open %s: %s\n", filename, strerror(errno));
+ exit(1);
+ }
+
+ ret = fread(&ehdr, sizeof(ehdr), 1, fp);
+ if (ret != 1) {
+ fprintf(stderr, "read error (%s)\n", filename);
+ exit(1);
+ }
+
+ if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
+ ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
+ ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
+ ehdr.e_ident[EI_MAG3] != ELFMAG3) {
+ fprintf(stderr, "not an elf file (%s)\n", filename);
+ exit(1);
+ }
+ if (ehdr.e_ident[EI_CLASS] != ELFCLASS64) {
+ fprintf(stderr, "elf class mismatch (%s)\n", filename);
+ exit(1);
+ }
+ if (ehdr.e_shoff == 0) {
+ fprintf(stderr, "no section header (%s)\n", filename);
+ exit(1);
+ }
+
+ /* read string table */
+ if (ehdr.e_shstrndx == 0) {
+ fprintf(stderr, "no section strings (%s)\n", filename);
+ exit(1);
+ }
+ str = elf_read_section(fp, &ehdr, ehdr.e_shstrndx, &str_size);
+ if (NULL == str) {
+ fprintf(stderr, "no section strings (%s)\n", filename);
+ exit(1);
+ }
+
+ /* find and read modinfo section */
+ info = NULL;
+ for (i = 0; i < ehdr.e_shnum; i++) {
+ elf_read_section_hdr(fp, &ehdr, i, &shdr);
+ if (!shdr.sh_name) {
+ continue;
+ }
+ if (strcmp(str + shdr.sh_name, ".modinfo") == 0) {
+ info = elf_read_section(fp, &ehdr, i, &info_size);
+ }
+ }
+ fclose(fp);
+
+ return modinfo(module, info, info_size);
+}
+
+int main(int argc, char **argv)
+{
+ DIR *dir;
+ FILE *fp;
+ ModuleInfo *modinfo;
+ ModuleInfoList *modlist;
+ Modules *modules;
+ Visitor *v;
+ QObject *obj;
+ Error *errp = NULL;
+ struct dirent *ent;
+ char *ext, *file, *name;
+ GString *gjson;
+ QString *qjson;
+ const char *json;
+
+ if (argc > 1) {
+ moddir = argv[1];
+ }
+
+ dir = opendir(moddir);
+ if (dir == NULL) {
+ fprintf(stderr, "opendir(%s): %s\n", moddir, strerror(errno));
+ exit(1);
+ }
+
+ modules = g_new0(Modules, 1);
+ while (NULL != (ent = readdir(dir))) {
+ ext = strrchr(ent->d_name, '.');
+ if (!ext) {
+ continue;
+ }
+ if (strcmp(ext, dsosuf) != 0) {
+ continue;
+ }
+
+ name = g_strndup(ent->d_name, ext - ent->d_name);
+ file = g_strdup_printf("%s/%s", moddir, ent->d_name);
+ modinfo = elf_parse_module(name, file);
+ g_free(file);
+ g_free(name);
+
+ modlist = g_new0(ModuleInfoList, 1);
+ modlist->value = modinfo;
+ modlist->next = modules->list;
+ modules->list = modlist;
+ }
+ closedir(dir);
+
+ v = qobject_output_visitor_new(&obj);
+ visit_type_Modules(v, NULL, &modules, &errp);
+ visit_complete(v, &obj);
+ visit_free(v);
+
+ gjson = qobject_to_json(obj);
+ qjson = qstring_from_gstring(gjson);
+ json = qstring_get_str(qjson);
+
+ file = g_strdup_printf("%s/modinfo.json", moddir);
+ fp = fopen(file, "w");
+ if (fp == NULL) {
+ fprintf(stderr, "open(%s): %s\n", file, strerror(errno));
+ exit(1);
+ }
+ fprintf(fp, "%s", json);
+ fclose(fp);
+
+ printf("%s written\n", file);
+ g_free(file);
+ return 0;
+}
diff --git a/meson.build b/meson.build
index d2a9ce91f556..9823c5889140 100644
--- a/meson.build
+++ b/meson.build
@@ -2380,6 +2380,17 @@ if xkbcommon.found()
dependencies: [qemuutil, xkbcommon], install:
have_tools)
endif
+if config_host.has_key('CONFIG_MODULES')
+ qemu_modinfo = executable('qemu-modinfo', files('qemu-modinfo.c') + genh,
+ dependencies: [glib, qemuutil], install:
have_tools)
+ custom_target('modinfo.json',
+ input: [ softmmu_mods, block_mods ],
+ output: 'modinfo.json',
+ install: true,
+ install_dir: qemu_moddir,
+ command: [ qemu_modinfo, '.' ])
+endif
+
if have_tools
qemu_img = executable('qemu-img', [files('qemu-img.c'), hxdep],
dependencies: [authz, block, crypto, io, qom, qemuutil], install:
true)
--
2.31.1
