Move source files to src/

src/inject_errors.c

@@ -0,0 +1,112 @@
+
+#define _GNU_SOURCE /* for RTLD_NEXT */
+#include <assert.h>
+#include <dlfcn.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+static FILE *fail;
+static FILE *fail_read;
+static FILE *fail_write;
+static FILE *fail_close;
+static int error;
+
+static FILE * (*real_fopen)(const char *, const char *);
+static int           (*real_fclose)(FILE *);
+static int           (*real_ferror)(FILE *);
+static void          (*real_clearerr)(FILE *);
+static char *        (*real_fgets)(char *, int, FILE *);
+static size_t        (*real_fread)(void *, size_t, size_t, FILE *);
+static size_t        (*real_fwrite)(const void *, size_t, size_t, FILE *);
+
+#define GET_REAL(sym)                         \
+  do {                                        \
+    if (real_ ## sym == 0) {                  \
+      real_ ## sym = dlsym(RTLD_NEXT, #sym);  \
+      assert(real_ ## sym != 0);              \
+    }                                         \
+  } while (0)
+
+#define dbg_write(msg) (void)write(2, msg, sizeof(msg) - 1)
+
+#define dbg() \
+  do {                                      \
+    dbg_write("here: ");                    \
+    dbg_write(__func__);                    \
+    dbg_write("!\n");                       \
+  } while (0)
+
+FILE *fopen(const char *path, const char *mode) {
+  GET_REAL(fopen);
+  fail = fail_read = fail_write = fail_close = 0;
+  FILE *f = real_fopen(path, mode);
+  error = EIO;
+  if (strcmp(path, "fail_read") == 0) {
+    fail = fail_read = f;
+  } else if (strncmp(path, "fail_write", sizeof("fail_write") - 1) == 0) {
+    // Not that jq opens files for write anyways...
+    fail = fail_write = f;
+    if (strcmp(path, "fail_write_enospc") == 0)
+      error = ENOSPC;
+  } else if (strncmp(path, "fail_close", sizeof("fail_close") - 1) == 0) {
+    fail = fail_close = f;
+    if (strcmp(path, "fail_close_enospc") == 0)
+      error = ENOSPC;
+  }
+  return f;
+}
+
+int fclose(FILE *f) {
+  GET_REAL(fclose);
+  int res = real_fclose(f);
+  if (fail_close == f) {
+    fail = fail_read = fail_write = fail_close = 0;
+    return EOF;
+  }
+  return res;
+}
+
+char * fgets(char *buf, int len, FILE *f) {
+  GET_REAL(fgets);
+  char *res = real_fgets(buf, len, f);
+  if (fail_read == f)
+    return 0;
+  return res;
+}
+
+size_t fread(void *buf, size_t sz, size_t nemb, FILE *f) {
+  GET_REAL(fread);
+  size_t res = real_fread(buf, sz, nemb, f);
+  if (fail_read == f)
+    return 0;
+  return res;
+}
+
+size_t fwrite(const void *buf, size_t sz, size_t nemb, FILE *f) {
+  GET_REAL(fwrite);
+  size_t res = real_fwrite(buf, sz, nemb, f);
+  if (fail_write == f)
+    return 0;
+  return res;
+}
+
+int ferror(FILE *f) {
+  GET_REAL(ferror);
+  int res = real_ferror(f);
+  if (fail == f) {
+    errno = error;
+    return 1;
+  }
+  return res;
+}
+
+void clearerr(FILE *f) {
+  GET_REAL(clearerr);
+  real_clearerr(f);
+  if (fail == f) {
+    fail = fail_read = fail_write = fail_close = 0;
+    error = 0;
+  }
+}